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ICIQ PhD Day 2019
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OUTLINE
Acknowledgements…………………………………………………….3
Invited speakers……….…………………………….………………….5
Organizing Committee…………………………….………………….7
Schedule…………………………….……………………………………..9
Flash presentation (Session 1)…………………………………….13
Flash presentation (Session 2)………………………..………….23
Flash presentation (Session 3)………………………………..….29
Poster Presentations..………………………………………………..38
ICIQ PhD Day 2019
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Acknowledgements
Welcome to the third ICIQ PhD Day.
First of all, we would like to thank you for participating in this home-made
event and for sharing and discussing your scientific results through oral or
poster presentation.
In addition to your contributions, we will attend invited lectures that will cover
different aspects of the role of a chemist in the modern community, such as
outreaching, academia, industry or entrepreneurship. This would have been
impossible without the contribution of all the invited speakers.
This meeting is organized and hosted by the Institute of Chemical Research of
Catalonia and sponsored by Serviquimia. We are extremely grateful for their
financial support.
The planning and organization of an event such as this one is always an
adventure because of the details and issues that have to be planned and
managed. This would have not been possible without the help of Ariadna
Goenaga, Judit Martínez and the precious advices from the organizing
committee of the previous ICIQ PhD Day.
Last but not least, we would like to thank the direction of the ICIQ for making
this event possible.
We wish you will enjoy this event.
The organizing committee
ICIQ PhD Day 2019
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ICIQ PhD Day 2019
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Invited Speakers
Dr. Cristina Sáenz de Pipaón (Orchestra Scientific)
Cristina is one of the founder members of Orchestra
Scientifics and its CEO. Orchestra Sci. is an ICIQ-
participated spin-off created with the aim of developing and
bringing to the market patent inventions by ICIQ’s Galán-
Mascarós group, where Cristina did a postdoctoral stay.
Orchestra was ICIQ’s first spin-off company and it serves as
an example of technology transfer of research results to the
industry.
Dr. Fernando Gomollón (Graphene Flagship)
PhD in Organic Chemistry and science communicator. He’s
currently the Press and Communications Coordinator of
the Graphene Flagship, one of the biggest EU funded
projects with a budget of €1bn. He also collaborates
periodically with ‘En Ruta con la Ciencia’, Tercer Milenio,
and Chemistry World. Fernando was ICIQ’s Press Officer
from 2016 to 2018.
Dr. Bibiana Campos (C&EN)
Bibiana acquired wide experience in the publishing industry
while working at the Royal Society of Chemistry, the
European Respiratory Society and Advanstar
Communications. Currently, she is the Editor in Chief and
VP of Chemical & Engineering News (C&EN) of the Media
Group. C&EN produces comprehensive and
authoritative journalism about the world of chemistry,
including coverage of recent research advances, chemical
safety practices, industry, funding and policy trends. C&EN
has been published by the American Chemical Society since
1923.
ICIQ PhD Day 2019
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Nessa Carson (Pfizer)
Nessa Carson is a high-throughput experimentation
chemist who uses lab robotics for reaction optimization in
drug discovery. Her background is in synthetic organic
chemistry, in which she earned Master’s degrees from
Oxford University and the University of Illinois at Urbana-
Champaign. Nessa can be found online as SuperScienceGrl,
and claims to have gained all of her career moves from
Twitter.
Dr. Jesús Campos (IIQ)
Jesús studied Chemistry at University of Sevilla and then he
moved to the University of Manchester (MPhil, Prof. John
D. Sutherland, 2008). Back to Spain he worked on
fundamental organometallic chemistry (Prof. Ernesto
Carmona), obtaining an International PhD Distinction
(2012). He then worked in green catalysis and energy-
related transformations as a postdoctoral researcher (Prof.
Robert H. Crabtree, Yale University). After a second
postdoctoral period (Talentia Postdoc Fellowship, Prof.
Simon Aldridge, University of Oxford), in 2016 he moved
back to the University of Sevilla (Marie Curie IF fellowship).
One year later he was awarded with a permanent position as
Research Scientist of the Spanish National Research
Council (CSIC) to develop his independent career at the
Institute of Chemical Research (IIQ) at Sevilla.
Dr. Matthieu Tissot (UCB)
Matthieu received his PhD degree in Chemistry from the
University of Geneva (Switzerland) under the supervision of
Prof. Alexakis working on asymmetric catalysis. After a
postdoctoral position with Prof. Gaunt focused on the total
synthesis of Morphine at the University of Cambridge (UK),
Matthieu joined GlaxoSmithKline (UK) as process chemist
developing new synthetic routes for active pharmaceutical
ingredients. In 2016, he joined UCB Pharma (Belgium) in
their discovery department, where he is implementing new
enabling flow chemistry technologies and tools to support
the delivery of lead candidates from medicinal chemistry
projects.
ICIQ PhD Day 2019
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Organizing Committee
Pablo Bonilla Domínguez: He graduated in Madrid and
received his MSc by Research from The University of
Manchester. Currently he is on his third year of PhD in the
group of Prof. Paolo Melchiorre working on the developing new
photo-organocatalytic cascade reactions for the synthesis of
enantiopure molecules.
Miguel Claros Casielles: He graduated in the University of
Oviedo and obtained his Master degree under the supervision
of Mª Pilar Gamasa. He joined the group of Prof. Julio Lloret
Fillol for his PhD under the supervision of Julio Lloret and
Alicia Casitas. He is currently studying the design of new
methodologies for the activation of strong bonds using visible
light as a source of energy.
Federico Dattila. He got his Master Degree in Physics from
the University of Turin after a 9 months-Erasmus at Chalmers
University of Technology (Gothenburg, Sweden). Currently, he
is a PhD student in computational chemistry under the
supervision of Prof. Nuria López and Dr. Rodrigo García-
Muelas. His investigation, within the European Project
ELCoREL, is devoted to electrochemical CO2 reduction
toward useful chemicals.
Ana G. Herraiz: She graduated in the University
Complutense of Madrid and received her MChem from the
University of Groningen. After an internship at the
pharmaceutical company Eli Lilly, she joined the group of Dr.
Marcos G. Suero to carry out her PhD studies on the discovery
of new carbon-based reactive species.
ICIQ PhD Day 2019
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José Enrique Gómez: Graduated with MSc degree from the
University of Valladolid. Since 2015, he has been a PhD student
at ICIQ focused on transition-metal-catalyzed stereocontrolled
transformations in the group of Prof. Arjan Kleij. During 2018
he joined Eli Lilly (UK) working on the development of
automatic structural elucidation platforms as a PhD visiting
student.
Joan G. Mayans: He graduated in Valencia and received his
Master degree in Strasbourg. He joined the group of Prof.
Antonio M. Echavarren for his PhD and he is currently
studying the behavior of different polyunsaturated molecules
in the presence of various catalytic systems based on gold.
Daniele Mazzarella: He graduated in Rome and received his
Master degree in Bologna. He also spent one year in Japan
working on the production of chemicals from non-edible
biomass. Since 2016 he is part of the group of Prof. Paolo
Melchiorre and he is currently developing new photo-
organocatalytic protocols for the production of
enantioenriched molecules.
Andrea Moneo Corcuera. She graduated with MSc degree
from the University of Zaragoza. In 2017, she joined the group
of Prof. Jose Ramón Galán-Mascarós for her PhD and she is
currently working on the discovery of novel bistable magnetic
molecules.
Andreu Tortajada. He graduated from University of
Valencia in 2015. Then, he joined the group of Prof. Ruben
Martin at ICIQ where he obtained his Master degree from the
Rovira i Virgili University and now he is studying towards a
PhD in the same group on the development of new metal-
catalyzed transformation for the incorporation of CO2 into
organic molecules.
ICIQ PhD Day 2019
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ICIQ PhD Day 2019
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Schedule
June 6th 2019
June 7th 2019
9:15 Nessa Carson
(Freelance Science)
10:00 Dr. Jesús Campos
(Academia Related)
10:45 Coffee Break
11:15 Flash Presentations
12:00 Registration 12:15
Dr. Bibiana Campos (Publishing)
13:00 Lunch
14:30 Opening Ceremony
Prof. Emilio Palomares (ICIQ) 14.30 Flash Presentations
15:00 Dr. Fernando Gomollón Bel
(Scientific Outreach) 16.00
Dr. Cristina Sáenz de Pipaón (Industry Related)
15:45 Dr. Matthieu Tissot (Industry Related)
16.45 Panel Discussion
“Social Networks in Science”
16:30 Coffee Break 17.30 Closing Ceremony
17:00 Flash Presentations 18.00 Poster Session and Aperitif
18:30 Poster Session
21.00 Conference Dinner
19:30 End of the day
ICIQ PhD Day 2019
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Flash presentations
Session 1: Thursday, June 6th 2019, 17:00 – 18:30 h
Title Speaker Research
Group
Halogen Catalysis for Selective sp3 C-H Amination (Hofmann-Löffler Reaction)
A. T. Duhamel K. Muñiz
Designing New Efficient Ru Based Molecular Water Oxidation Catalysts
N. Vereshchuk A. Llobet
Photochemical Generation of Radicals
from Electrophiles Using a Nucleophilic Organic Catalyst
E. de Pedro Beato P. Melchiorre
A Mechanistic Study towards the
Identification of the Key Steps Involved in the Cobalt-Catalyzed Reduction of
CO2 to CO
S. Fernandez J. Lloret
New Applications of 1,7-Enynes on the
Gold(I)-Catalysed Synthesis of Hydroacene Derivatives
O. Stoica A. Echevarren
Solar-Driven Water Splitting: from
Molecular Catalysts to
Photoelectrochemical Cells
M. Ventosa A. Llobet
Rational Design of Cp*CoIII-Catalyzed
C–H Functionalizations Based on Fundamental Knowledge
J. Sanjosé-Orduna
M. H. Perez Temprano
Immobilization of cis-4-
Hydroxydiphenylprolinol Silyl Ethers onto Polystyrene
J. Lai M. Pericas
Light-Driven Competitive Reduction of
Aromatic Ketones vs Aromatic Olefins in Aqueous Media
D. Pascual J. Lloret
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Session 2: Friday, June 7th 2019, 11:15 – 12:15 h
Title Speaker Research
Group
Gold-Cavitand Catalysts for the Selective Cyclization of Enynes
I. Martín A. M. Echavarren
A New Family of Tetradentated N-Based Ni/Co Complexes for the Development
of Visible-light Metallaphotoredox Strategies
J. Aragón J. Lloret-Fillol
Catalytic Cleavage of Strong Carbon-
carbon Bonds with Rhodium-Carbyne Equivalents
P. Sarró M. García Suero
A Mild and Direct Site-Selective sp2 C-H
Silylation of (Poly)Azines
Y. Gu R. Martín
Spin Crossover into Switchable
Multifunctional Materials
D. Nieto J. R. Galán-
Mascarós
ICIQ PhD Day 2019
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Session 3: Friday, June 7th 2019, 14:30 – 16:00 h
Title Speaker Research
Group
Theoretical Mechanistic Studies in Rh-Cu Bimetallic Cooperation: Beyond Two
Interlinked Cycles
A. L. Mudarra F. Maseras
Iodine-Catalyzed Intermolecular Csp3-H Amination.
A. E. Bosnidou K. Muñiz
Electrocatalytic CO2 Reduction with MDn Molecular Sites into Covalent-
Organic Frameworks.
G. C. Dubed J. Lloret-Fillol
Metallaphotoredox Carbamoylation of
(Hetero)Aryl Bromides.
N. Alandini P. Melchiorre
Overriding Old Conceptions: Formal
Synthesis of Indolizidine and Quinolizidine Alkaloids from Cyclic
Carbonates.
A. Cristòfol A. W. Kleij
Enantioselective Synthesis of Nicotine
via an Iodine-Mediated Hofmann-Löffler Reaction.
E. Del Castillo K. Muñiz
Molecular Water Oxidation Catalysts for Photo-Electrochemical Water Splitting.
L. Riccardi A. Llobet
Self-Assembly of Homo- and
Heterodimeric Capsules Based on a Tetraspiropyran Tetraurea
Calix[4]arene.
G. Moncelsi P. Ballester
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Flash presentations
Session 1
Thursday, June 6th 2019, 17:00 – 18:30 h
ICIQ PhD Day 2019
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Halogen Catalysis for Selective sp3 C-H Amination (Hofmann-Löffler Reaction)
A. T. Duhamel,a K. Muñiz.a*
a Institut Català d’Investigació Química, The Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, Tarragona, Spain.
tduhamel@iciq.es
Four effective protocols for such catalytic Hofmann-Löffler reactions have
been designed based on molecular iodine1 or an ammonium bromide salt2 as pre-catalyst in the presence of oxidants. Engineering optimized catalysis conditions, under which hypoiodite ROI(I) or hypobromite ROBr(I) are in-situ formed, represents the challenging aspect for the in-situ generation of the N-halogenated intermediate A (Figure 1). The innate reactivity of such key N-X intermediates A under visible light enables the formation of the amidyl radical B, which promotes a selective remote C-H functionalization through a 1,5-hydrogen atom transfer (HAT). The intermediate C-centered radical C then undergoes halogenation through a radical chain mechanism. Depending on the reactivity degree at the respective halogenated carbon of D, immediate cyclization can occur at this stage through the nitrogen nucleophile (red pathway). Alternatively, suitably engineered oxidation to an intermediary alkyl iodide(III) E may be pursued (green pathway). It is known that iodine(III) acts as an excellent nucleofuge, and this capacity accelerates the cyclization step to the corresponding pyrrolidine products.
Catalytic cycle for the halogen catalyzed Hofmann-Löffler reaction References [1] (a) Martínez, C.; Muñiz, K. Angew. Chem. Int. Ed. 2015, 54, 8287. (b) Becker, P.; Duhamel, T.; Stein, C. J.; Reiher, M.; Muñiz, K. Angew. Chem. Int. Ed. 2017, 56, 8004. (c) Duhamel, T.; Stein, C. J.; Martínez, C.; Reiher, M.; Muñiz, K. ACS Catal. 2018, 8, 3918. [2] Duhamel, T.; Becker, P.; Martínez, C.; Muñiz, K. Angew. Chem. Int. Ed. 2018, 57, 5166.
ICIQ PhD Day 2019
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Designing New Efficient Ru Based Molecular Water Oxidation Catalysts
N. Vereshchuk,a,b R. Matheu,a,b J. Benet-Buchholz,a M. Pipelier,c J. Lebreton,c D. Dubreuil,c A. Tessier,c C. Gimbert-Surinach,a M. Z. Ertem,d A. Llobet.a,e
a Institut Català d’Investigació Química, The Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, Tarragona, Spain.
b Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, Spain c Université de Nantes, France
d, Brookhaven National Laboratory, USA e Departament de Química, Universitat Autònoma de Barcelona, Spain
nvereshchuk@iciq.es
Developing a sustainable global energy currency is considered one of the major
challenges facing researchers today. Future sustainable energetic schemes rely on technologies that store energy into chemical bonds. The resulting solar fuels are produced from abundant substrates such as water, carbon dioxide, or nitrogen.1,2
There are still a lot of investigation to be done in this field, before the efficient commercially viable solution will be realized. Our group has been at the forefront of this area of research for many years and particular attention is being paid to the water oxidation, which is a bottleneck process in solar fuel technologies. The most efficient WOCs known today are based on the Flexible Adaptative Multidentate Equatorial ligands containing polypyridyl carboxylate groups such as H2tda and H2bda.3,4
A new re-design Ru catalyst has been prepared and characterized by spectroscopic and electrochemical methods. Comparative studies of the catalytic activities for different kind of ligand design has provided a better understanding of the mechanisms for water oxidation as well as catalyst degradation. Further, we show that these new Ru based complexes can achieve water oxidation catalysis driven chemically, electrochemically or photochemically.
References [1] Matheu, R.; Ertem, M. Z.; Gimbert-Suriñach, C.; Sala, X.; Llobet, A. Chem. Rev., 2019, 119, 3453–3471. [2] Garrido-Barros, P.; Gimbert-Suriñach, C.; Matheu, R.; Sala, X.; Llobet, A. Chem. Soc. Rev., 2017, 46, 6088-6098. [3] Matheu, R.; Ertem, M. Z.; Benet-Buchholz, J.; Coronado, E.; Batista, S. V.; Sala, X.; Llobet, A. J. Am. Chem. Soc., 2015, 137 , 10786–10795. [4] Richmond, C. J.; Matheu, R.; Poater, A.; Falivene, L.; Benet-Buchholz, J.; Sala, X.; Cavallo, L.; Llobet, A., Chem. - A Eur. J. 2014, 20, 17282–17286.
ICIQ PhD Day 2019
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Photochemical Generation of Radicals from Electrophiles Using a Nucleophilic Organic Catalyst
E. de Pedro Beato,a B. Schweitzer-Chaput,a M. A. Horwitz,a P. Melchiorre.a,b
a Institut Català d’Investigació Química, The Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, Tarragona, Spain.
b IIT, via Morego 30 – 16163 Genoa, Italy
edepedro@iciq.es
The field of radical chemistry has experienced a recent revival thanks to the
emergence of photoredox catalysis, which allows the generation of radical intermediates under mild conditions.1
Here we report a novel photochemical catalytic strategy to generate radicals from a variety of typically unreactive electrophilic compounds. We use a nucleophilic dithiocarbamate anion catalyst 1, adorned with a well-tailored chromophoric unit, to activate alkyl electrophiles via an SN2 pathway. The resulting photon-absorbing intermediate affords radicals upon homolytic cleavage induced by visible light.2
Unlike previous strategies using dithiocarbonyl compounds as stoichiometric reagents,3 we could achieve catalysis by designing suitable turn-over events to regenerate the catalytically active anion 1. The concept of dithiocarbamate anion catalysis was applied to several transformations, including radical conjugate additions, alkylations of (hetero)aromatic substrates, asymmetric α-alkylation of aldehydes and the functionalization of complex bioactive substrates.
Radical generation strategy.
References [1] Prier, C. K.; Rankic, D. A.; MacMillan, D. W. C., Chem. Rev. 2013, 113, 5322-5363. [2] Schweitzer-Chaput, B., Horwitz, M. A., de Pedro Beato, E.; Melchiorre, P. Nat. Chem. 2019, 11, 129–135. [3] Quiclet-Sire, B.; Zard, S. Z., Chem. Eur.J. 2006, 12, 6002.
ICIQ PhD Day 2019
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A Mechanistic Study Towards the Identification of the Key Steps Involved in the Cobalt-Catalyzed Reduction of CO2 to CO
S. Fernández,a F. Franco,a C. Casadevall,a V. Martin-Diaconescu,a J. M. Luis,c*
J. Lloret-Fillol.a,b*
aInstitute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Avinguda Països Catalans 16, 43007, Tarragona, Spain.
bCatalan Institution for Research and Advanced Studies (ICREA), Lluïs Companys, 23, 08010, Barcelona, Spain.
cInstitut de Química Computacional i Catàlisi (IQCC), Departament de Química, Campus Montilivi s/n, 17007, Girona, Spain.
sfernandez@iciq.es
In the last years, pyridine-based Co complexes have emerged as active
catalysts in the CO2-to-CO reduction process under both photo- and electrochemical conditions.1 However, investigations to fully understand the reaction mechanism and its bottlenecks have yet to be adressed.2 We have studied the electrochemical CO2 reduction process catalyzed by complex 1(II).3 The combination of cyclic voltammetry and in-situ spectroelectrochemistry allowed for the detection of a [LN4CoI-CO]+ (1(I)-CO) intermediate at the CoII/I redox wave under CO2 atmosphere in anhydrous MeCN. The detection of this intermediate implies a first CO2 binding to CoI and a subsequent C-O bong cleavage at the same CoII/I redox potential. A DFT analysis of the reaction mechanism revealed that the rate determining step of the catalytic reaction involves the CO release from 1(I)-CO, which prevents the recovery of the catalytically active species. Further theoretical insights at the CoI/0 redox potential predict that only the protonation events contribute to the energy of the barrier. Finally, we propose the use of blue-light irradiation under bulk electrolysis conditions as a strategy to recover the catalitically active species via light-induced metal-carbonyl dissociation.4
CO2. Proposed reaction mechanism based on DFT, CV and IR-SEC. References [1] Takeda, H.; Cometto, C.; Ishitani, O.; Robert, M. ACS Catal. 2017, 7, 70. [2] Chambers, M. B.; Wang, X.; Fontecave, M. Chem. Soc. Rev. 2017, 46, 761. [3] Call, A.; Franco, F.; Kandoth, N.; Fernández, S.; González-Béjar, M.; Pérez-Prieto, J.; Luis, J. M., Lloret-Fillol. J. Chem. Sci., 2018, 9, 2609. [4] Fukatsu, A.; Kondo, M.; Okabe, Y.; Masaoka, S. J. Photochem. Photobiol. A, 2015, 313, 143.
ICIQ PhD Day 2019
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Applications of 1,7-Enynes on the Gold(I)-Catalysed Synthesis of Hydroacene Derivatives
O. Stoica,a,b R. Dorel,a,b A. M. Echavarren.a,b
a Institut Català d’Investigació Química, The Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, Tarragona, Spain.
b Departament de Química Analítica i Química Orgànica, Universitat Rovira i Virgili, C/Marcel·li Domingo s/n, 43007 Tarragona, Spain.
ostoica@iciq.es
Acenes are a class of aromatic hydrocarbons composed of linearly fused
benzene rings that have been broadly investigated due to their distinctive electronic properties, which make them appealing candidates for use in molecular electronics.[1] Consequently, uncovering new methods for the preparation of acene derivatives has been of great interest recently.[2]
In this regard, we have previously developed an efficient methodology to synthesise partially hydrogenated acenes, based on the Au(I)-catalysed intramolecular [4+2] cycloaddition of 1,7-enynes as the key step.[3] We now aim at expanding this method to access larger and also functionalised hydroacenes with improved solubility and stability. Hence, a second generation of larger and also doubly-substituted enyne precursors have been developed for the preparation of new acene-based materials.
References [1] Anthony, J. E. Angew. Chem. Int. Ed. 2008, 47, 452. [2] Dorel, R.; McGonigal, P. R.; Echavarren, A. M. Angew. Chem. Int. Ed. 2016, 55, 11120. [3] Dorel, R.; Echavarren, A. M. Eur. J. Org. Chem. 2017, 14.
ICIQ PhD Day 2019
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Solar-Driven Water Splitting: from Molecular Catalysts to
Photoelectrochemical Cells
M. Ventosa,a C. Gimbert-Suriñach, a A. Llobet.a*
a Institut Català d’Investigació Química, The Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, Tarragona, Spain.
mventosa@iciq.es
Water reduction and water oxidation catalysts are the key for light-induced
water-splitting devices. Current designs are based on metals such as Pt or Ni for the hydrogen evolution reaction (HER) and metal oxides for the oxygen evolution reaction (OER).1 In recent years, the field of molecular catalysts for HER and OER have grown due to the well understanding of the mechanisms of the catalytic reactions.2 Furthermore, molecular catalysts have the potential to tune their activity and robustness by modifying the ligands in the coordination sphere. The lack of long-term stability of the molecular catalysts hinders their implementation into a complete photoelectrochemical cell (PEC). This drawback can be overcome by heterogenization of the molecular catalysts following different strategies.3,4
The present work attempts to bridge the fields of heterogeneous and molecular catalysis by polymerization of a water oxidation molecular catalyst, modified with thiophene groups. The new material combines the robustness of heterogeneous polymers and the efficiency and selectivity of the well-known active sites. This is the first step towards an applicable solar-driven water splitting device.
References [1] Montoya J.H.; Seitz, L.C.; Chakthranont, P.; Vojvodic, A.; Jaramillo, T.F.; Nørskov, J.K. Nature Materials 2016, 16, 70. [2] Berardi, S.; Drouet, S.; Francàs, L.; Gimbert-Suriñach, C.; Richmond, C.; Stoll, T.; Llobet, A. Chem. Soc. Rev. 2014, 43, 7501. [3] Zhang, B.; Sun, L. Chem. Soc. Rev. 2019, 2216–2264. [4] Costentin, C.; Savéant, J. Current Opinion in Electrochemistry 2019, 4, 1.
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Rational Design of Cp*CoIII-Catalyzed C–H Functionalizations Based on Fundamental Knowledge
J. Sanjosé-Orduna,a J. M. Sarria Toro,a M. H. Pérez-Temprano.a*
a Institute of Chemical Research of Catalonia (ICIQ) The Barcelona Institute of Science and Technology
(BIST) Av. Països Catalans 16 – 43007 Tarragona (Spain).
jsanjose@iciq.es
Beyond any doubt, the selective functionalization of inert C–H bonds of
petroleum-based derivatives is one of the holy grails in synthetic chemistry. In the past decades, noble transition metals have played a key role in this kind of transformations. However, in the past few years, more cost-effective first-row transition metals, such as cobalt, have emerged as an attractive alternative to precious metals.1
Over the past few years, the employment Cp*CoIII complexes, analogous to active RhIII catalysts for C–H activation, has represented a tremendous advance in cobalt catalysis.2 When compared to noble metals, cobalt catalysts offer obvious advantages, including being earth-abundant and cheaper. However, without any doubt, the most interesting feature of cobalt catalysts is the potential rich manifold of reactivity patterns that they can provide, not only mimicking precious metals but also exhibiting a unique and versatile reactivity due to its low electronegativity and the facile access to multiple oxidation states through 1 or 2 electron processes.
Despite this significant progress, these CoIII systems are still at their infancy when compared to Rh- and Pd-based catalysts, and fundamental questions, specially concerning the underlying reaction mechanisms, remain unsolved.
This presentation will disclose our recent efforts on the development of more efficient Cp*CoIII-catalyzed C–H functionalization reactions based on knowledge-driven approaches.3
References [1] Gandeepan, P.; Müller, T.; Zell, D.; Cera, G.; Warratz, S.; Ackermann, L. Chem. Rev. 2019, 119, 2192. [2] (a) Yoshino, T.; Matsunaga, S. Adv. Synth. Catal. 2017, 359, 1245. (b) Chirila, P. G.; Whiteoak, C. J. Dalton Trans. 2017, 46, 9721 [3] (a) Sanjosé-Orduna, J.; Gallego, D.; Garcia-Roca, A.; Martin, E.; Benet-Buchholz, J.; Pérez-Temprano, M. H. Angew. Chem. Int. Ed. 2017, 56, 12137. (b) Sanjosé-Orduna, J.; ‡ Sarria, J. M.; ‡ Pérez-Temprano, M. H. Angew. Chem. Int. Ed. 2018, 57, 11369.
Advantages:
(i) cost-effective
alternative to Rh(III)
(ii) unique reactivity
and selectivity
Current limitations:
limited understanding of
the nature of the reactive
species or mechanism
cat. [Cp*CoIII]
additives
C−H activation
[CoIII]DG
H
DG DG
knowledge building block for rational design
ICIQ PhD Day 2019
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Immobilization of cis-4-Hydroxydiphenylprolinol Silyl Ethers onto Polystyrene. Application in the Catalytic Enantioselective Synthesis of
5-Hydroxyisoxazolidines in Batch and Flow
J. Lai,a,c S. Sayalero,a A. Ferrali,a L. Osorio-Planes,a F. Bravo,a C. Rodríguez-Escrich,*,a
and M. A. Pericàs.*a,b
a Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and
Technology, Av. Països Catalans, 16, 43007 Tarragona (Spain). b Departament de Química Inorgànica i Orgànica, Universitat de Barcelona (UB), 08028 Barcelona
(Spain). c Universitat Rovira i Virgili, Departament de Química Analítica i Química Orgànica, c/Marcel·lí
Domingo, 1, 43007 Tarragona, Spain
jlai@iciq.es
A new family of polystyrene‐supported cis‐4‐hydroxydiphenyl-prolinol silyl ethers has been prepared,1 and the resulting polymers have been evaluated as organocatalysts to promote the tandem reaction between N‐protected hydroxylamines and α,β‐unsaturated aldehydes in batch and flow. Immobilized diarylprolinol 1c, has afforded the best results while proving remarkably stable under the reaction conditions. This has allowed to run ten consecutive cycles of the same reaction, providing the same enantioselectivity and without significant loss of yield. In addition, eleven flow experiments involving nine different substrates have been carried out over a period of 2 months with the same packed column. The new PS‐supported catalysts compare favorably with well‐established immobilized Jørgensen‐Hayashi catalysts,2 affording 5‐hydroxy-isoxazolidines as single diastereoisomers with high enantioselectivities and good yields (up to 83% yield, up to 99% ee).
References [1] Lai, J.; Sayalero, S.; Ferrali, A.; Osorio‐Planes, L.; Bravo, F.; Rodríguez‐Escrich, C.; Pericàs, M.A. Adv Synth Catal. 2018, 360, 2914-2924. [2] a) Riente, P.; Mendoza, C.; Pericàs, M. A. J. Mater. Chem. 2011, 21, 7350-7355; b) Alza, E.; Sayalero, S.; Cambeiro, X. C.; Martín-Rapún, R.; Miranda, P. O.; Pericàs, M. A. Synlett 2011, 464-468; c) Fan, X. Sayalero, S. Pericàs, M. A. Adv. Synth. Catal. 2012, 354, 2971-2976; d) Fan, X.; Rodríguez‐Escrich, C.; Sayalero, S.; Pericàs, M. A. Chem. - Eur. J. 2013, 19, 10814-10817; e) Llanes, P.; Rodríguez‐Escrich, C.; Sayalero, S.; Pericàs, M. A. Org. Lett. 2016, 18, 6292-6295.
cat. 1c
R1
O
NH
OHR2
PhCOOH
+
NO
R1
OH
R2
50 µL min-1
50 µL min-1
Two-channel
syringe pump
Cat. 1c(1.0 g, 0.41 mmol)
ICIQ PhD Day 2019
23
Light-Driven Competitive Reduction of Aromatic Ketones vs Aromatic Olefins in Aqueous Media
D. Pascual,a C. Casadevall,a J. Lloret-Fillol.a*
a Institute of Chemical Research of Catalonia (ICIQ), Spain.
dpascual@iciq.es
A prerequisite for a sustainable society is the development of new efficient,
cheap and greener synthetic methods. The use of sun light as a source of energy is envisioned as one of the most sustainable approaches.1 Herein we present a catalytic system based on earth abundant-elements that selectively reduces aryl ketones in front of aryl olefins, using visible light as driving-force and H2O/amine as source of hydride. The catalytic system involves a robust and well-defined Co complex with an aminopyridine ligand2 and a Cu photoredox catalyst.3
Based on our mechanistic understanding, we envisioned that selectivity in the reduction of aromatic ketones4 versus aromatic olefins could be predictably tuned upon optimization of the catalytic conditions. Therefore, other photosensitizers and conditions were evaluated, reaching to a dual Co/Ir system capable of reducing all the aryl ketone with 100% selectivity before reacting with the aryl olefin. We envision that further optimization can lead to the inverse selectivity.
References [1] Lewis, N. S.; Nocera, D. G. Proc. Natl. Acad. Sci. U. S. A. 2006, 103, 15729-15735. [2] Call, A.; Codolà, Z.; Acuña-Parés, F.; Lloret-Fillol, J. Chem. Eur. J. 2014, 20, 6171-6183. [3] Luo, S. P.; Mejia, E.; Friedrich, A.; Pazidis, A.; Junge, H.; Surkus, A. E.; Jackstell, R.; Denurra, S.; Gladiali, S.; Lochbrunner, S.; Beller, M. Angew. Chem., Int. Ed. 2013, 52, 419-423. [4] Call, A.; Casadevall, C.; Acuña-Parés, F.; Casitas, A.; Lloret-Fillol, J. Chem. Sci. 2017, 8, 4739-4749.
ICIQ PhD Day 2019
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Flash presentations
Session 2
Friday, June 7th 2019, 11:15 – 12:15 h
ICIQ PhD Day 2019
25
Gold-Cavitand Catalysts for the Selective Cyclization of Enynes
I. Martín-Torres,a,b J.M. Yang,a A. M. Echavarren.a,b
a Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology (BIST) Av. Països Catalans 16, 43007 Tarragona (Spain).
b Departament de Química Analítica i Química Orgànica, Universitat Rovira i Virgili, C/Marcel·li Domingo s/n, 43007 Tarragona (Spain).
imartin@iciq.es
The design of new supramolecular entities that mimic the activity of enzymes
is an attractive approach for enhancing the selectivity of metal catalysts. Gold(I) cavitands have been reported as a good alternative for the cross-dimerization and hydration of alkynes.1 In our group, we are interested in unlocking new cyclization pathways of polyunsaturated substrates.2 Specifically, we are exploring the use of gold(I)-cavitand complexes, which contain a cavity that may force the enyne substrates to adopt a constrained conformation, leading to new selectivities in cycloisomerization reactions.
In this communication, we will present the design, synthesis and characterization of new gold(I)-cavitand complexes. The catalytic activity and new selectivities of these complexes in different cycloisomerization reactions will be discussed. Efforts towards the synthesis and application of chiral gold(I)-cavitands as asymmetric catalysts will also be presented.
Different reactivity in the gold(I)-catalyzed cyclization of enynes References [1] (a) Endo, N.; Inoue, M.; Iwasawa, T. Eur. J. Org. Chem. 2018, 1136–1140. (b) Endo, N.; Kanaura, M.; Schramm, M. P.; Iwasawa, T. Eur. J. Org. Chem. 2016, 2514–2521. [2] (a) Obradors, C.; Echavarren, A. M. Acc. Chem. Res. 2014, 47, 902–912. (b) Nieto-Oberhuber, C.; Muñoz, M. P.; López, S.; Jiménez-Núñez, E.; Nevado, C.; Herrero-Gómez, E.; Raducan, M.; Echavarren, A. M. Chem. Eur. J. 2006, 12, 1677–1693.
AgX, CH2Cl2, 0 ºC
Z
R2
R1
Z R2
R1
Z
R2
R1
[Au(PPh3)Cl]
AgX, CH2Cl2, 0 ºC
Typical Outcome New Selectivity
ICIQ PhD Day 2019
26
A New Family of Tetradentated N-based Ni/Co Complexes for the Development of Visible-light Metallaphotoredox Strategies
J. Aragón,a J. Benet-Buchholz,a A. Casitas,a J. Lloret-Fillol.a,b
a Institut Català d’Investigació Química, The Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, Tarragona, Spain.
b Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys, 23, 08010, Barcelona, Spain.
jaragon@iciq.es
Recent photoredox catalytic methodologies based on the visible-light-induced
generation of highly reactive radicals have allowed the construction of a large variety of selective C-C and C-heteroatom bonds.1,2 The inertness of chloroalkanes has precluded them as prevailing coupling partners in both conventional and photocatalytic cross-coupling reactions.
We have achieved the activation of unactivated Csp3-Cl bonds by means of a dual metal catalytic system based on earth-abundant metals (Cu, Co/Ni) and using visible-light as a source of energy. This bimetallic system has been employed to develop sustainable intramolecular reductive cyclization reactions of chloroalkanes with tethered alkenes/alkynes.3,4
Herein we disclose the synthesis of a family of tetradentate N-based Co and Ni complexes. The electronic properties of the metal center are modulated by the introduction of several electron-withdrawing and electron-donor substituents at the β- and γ- positions of the pyridine framework. Moreover, we bring to light the catalytic activity of this family of complexes in the aforementioned reactions. The ultimate goal of this project is to obtain the structure/activity relationship and understand the intermediates in the catalytic cycle in order to develop highly robust and efficient metal catalysts for the cleavage of strong σ-bonds.
References [1] Twilton, J.; Le, C.; Zhang, P.; Shaw, M.H.; Evans, R.W.; MacMillan D.W.C. Nat. Rev. 2017, 1,
0052. [2] Johnston, C.P.; Smith, R.T.; Allmendinger, S.; MacMillan, D.W.C. Nature. 2016, 536, 322. [3] (a) Kim, H.; Lee, C. Angew. Chem. Int. Ed. 2012, 51, 12303. (b) Revol, G.; McCallum, T.;
Morin, M.; Gagosz, F.; Barriault, L. Angew. Chem. Int. Ed. 2013, 52, 13342. [4] Claros, M.; Ungeheuer, F.; Franco, F.; Martin-Diaconescu, V.; Casitas, A.; Lloret-Fillol, J.
Angew. Chem. Int. Ed., 2019, 58, 4869.
ICIQ PhD Day 2019
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Catalytic carbyne insertion in an alkene to furnish functionalized dienes and allylic building blocks
Catalytic Cleavage of Strong Carbon-Carbon Bonds with Rhodium-Carbyne Equivalents
P. Sarró Grané,a Z. Wang,a L. Jiang,a M. García Suero.a*
a Institut Català d’Investigació Química, The Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, Tarragona, Spain.
psarro@iciq.es
In the last half century, the formation of organometallic species with metal-
carbon single and double bonds have been studied in depth and broadly used in reaction discovery and development of chemical synthesis. In the case of metal-carbon triple bonds, although there are multiple well-established strategies to synthesize them, their reactivity has been much less investigated and is centered basically on the alkyne methatesis processes. In this context, the development of new methods to generate metal-carbyne species or equivalent compounds would give rise to previously unknown transformations.
In order to address this problem, we wanted to create a system based on the catalytic generation of equivalent forms of metal-carbynes with the innate reactivity of a cationic monovalent carbon. Recently, our research group has designed stable carbyne sources formed by two leaving groups, a hypervalent iodine moiety and a diazo functional group, that under light/catalyst activation would unmask the carbyne equivalent.1 We found that when treating our carbyne equivalents with rhodium paddlewheel complexes, these carbine equivalents were able to cleave a C-C double bond in alkenes by formally inserting a cationic monovalent carbon between both C(sp2)-C(sp2). This process gives direct access to synthetically useful allyl cation intermediates that upon either proton elimination or nucleophile attack, lead to dienes or allylic building blocks respectively. Our results rely on the formation of cyclopropyl cation intermediates, which are able to undergo electrocyclic ring-opening following the Woodward-Hoffmann-DePuy rules.
References [1] Wang, Z.; Herraiz, A. G.; del Hoyo, A. M.; Suero, M. G. Nature 2018, 554, 86-91.
ICIQ PhD Day 2019
28
A Mild and Direct Site-Selective sp2 C-H Silylation of (Poly)Azines
Y. Gu,a,b Y. Shen,a,b C. Zarate,a,b R. Martin.a,b,c*
a Institute of Chemical Research of Catalonia (ICIQ), Spain. b Universitat Rovira i Virgili, Departament de Química Analítica i Química Orgànica, c/Marcel·lí
Domingo, 1, 43007 Tarragona, Spain. c ICREA, Passeig Lluïs Companys, 23, 08010, Barcelona, Spain.
ygu@iciq.es
(Poly)azines rank among the most prevalent motifs in a myriad of natural
products and compounds that display important biological properties.1 Not surprisingly, chemists have recently been challenged to develop a series of C–H functionalization reactions that allows to control the site-selectivity profile of the protocol, thus allowing to access a series of polysubstituted azines from simple precursors.2 As part of our interest in the functionalization of inert chemical bonds, we have recently discovered a base-mediated site-selective C-H silylation of (poly)azines.3 This method is distinguished by its mild conditions and experimental ease – even in the context of late-stage functionalization, while exhibiting orthogonal reactivity with classical silylation reactions.
References [1] (a) Blakemore, D. C.; Castro, L.; Churcher, I.; Rees, D. C.; Thomas, A. W.; Wilson, D. M.; Wood, A. Nat. Chem. 2018, 10, 383. (b) Vitaku, E.; Smith, D. T.; Njardarson, J. T. J. Med. Chem. 2014, 57, 10257. [2] (a) Murakami, K.; Yamada, S.; Kaneda, T.; Itami, K. Chem. Rev. 2017, 117, 9302. (b) Nakao, Y. Synthesis 2011, 20, 3209. [3] Gu, Y.; Shen, Y.; Zarate, C.; Martin, R. J. Am. Chem. Soc. 2019, 141, 127.
ICIQ PhD Day 2019
29
Spin Crossover into Switchable Multifunctional Materials
D. Nieto Castro,a F. Garcés-Pineda,a J. R. Galán-Mascarós.a,b*
a Institut Català d’Investigació Química, The Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, Tarragona, Spain.
b Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys, 23, 08010, Barcelona, Spain.
dnieto@iciq.es
Spin-crossover (SCO) materials have been extensively studied for their
potential applications in multiple fields, because of their unique bistability and switching features.1 These materials are typically molecular inorganic complexes of transition-metal cations with moderate crystal field ligands. This allows for the presence of a low-lying metastable high spin (HS) excited state that can be populated by external stimuli in the solid state. In the solid state cooperativity may arise when this electronic transition triggers a crystallographic transition, that may result in the appearance of thermal hysteresis. These features (and others) are powerful enough to establish a synergy in a composite material with a second property of interest, that may be affected by the effective electronic, spectroscopic, or chemical changes induced by the spin transition. Obviously, beyond the right selection of multi-components in the desired composite, the appearance of synergy will depend on the processing, that determines the final intermolecular and intercomponent interactions in the solid state.
Here we will present some plausible strategies in the search for SCO-based switchable hybrids exhibiting memory effect in diverse properties of interest in electronic transport. Our most recent results will illustrate the unique versatility and efficiency of SCO components to confer switchability to a wide variety of technology-ready materials, at room temperature and ambient conditions.
Thermal dependence of electrical conductivity in a PEDOT/SCO composite.
References [1] Bousseksou, A.; Molnar, G.; Salmon, L.; Nicolazzi, W. Chem. Soc. Rev. 2011, 40, 3313-3335.
ICIQ PhD Day 2019
30
Flash presentations
Session 3
Friday, June 7th 2019, 14:30 – 16:00 h
ICIQ PhD Day 2019
31
Theoretical Mechanistic Studies in Rh-Cu Bimetallic Cooperation: Beyond Two Interlinked Cycles
A. L. Mudarra,a I. Funes-Ardoiz,a F. Maseras.a,b
a Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology
(BIST), Av. Països Catalans 16, 43007 Tarragona, Spain.
b Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain.
amudarra@iciq.es
Direct C−H activation is a green alternative to cross-coupling reactions that allows the formation of a new C−C bond in a non-prefunctionalized position. In a non-neutral redox catalytic system, after reductive elimination, an oxidant is required. Different transition metals have been reported to be effective in these transformations but only with some selective oxidative partners. Recently, in our group, a perfect cooperation between Rh and Cu has been reported.1 Interestingly, the reductive elimination does not take place from a single metal center but from a Rh-Cu intermediate. Herein, we study computationally another example of bimetallic Rh and Cu system where two interlinked catalytic cycles are proposed to be taking place (Figure)2. However, microkinetic simulations point out a complete cooperation of both metals beyond the proposed cycles.
Schematic for the Rh-Cu catalytic transformation
References
[1] Funes-Ardoiz, I; Maseras, F. Angew. Chem. Int. Ed. 2016, 55, 2764. [2] Wang, Y. F.; Toh, K. K.; Lee, J. Y.; Chiba, S. Angew. Chem. Int. Ed. 2011, 50, 5927.
ICIQ PhD Day 2019
32
Iodine-Catalyzed Intermolecular Csp3-H Amination
A. E. Bosnidou,a K. Muñiz.a,b*
a Institut Català d’Investigació Química, The Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, Tarragona, Spain.
b Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys, 23, 08010, Barcelona, Spain.
abosnidou@iciq.es
The direct installation of an amino functional group on organic molecules
through a direct C-H activation is an issue that has received particular attention in synthetic organic chemistry. Over the past decade, several transition-metal catalyzed processes were reported.1
An interesting and green alternative to these pathways includes the use of hypervalent iodine (III) reagents. A combination of molecular iodine with these reagents was reported recently from our group for the synthesis of pyrrolidines through intramolecular amination reaction.2 In this context, a selective intermolecular amination of saturated hydrocarbons with sulfonamides will be discussed.3 The development of a surprisingly general methodology as well as application in the synthesis of pharmaceutical compounds will be presented.
References [1] Park, Y.; Kim, Y.; Chang, S. Chem. Rev. 2017, 117, 9247-9301. [2] Martínez, C.; Muñiz, K. Angew. Chem. Int. Ed. 2015, 54, 8287-8291. [3] Bosnidou, A. E.; Muñiz, K. Angew. Chem. Int. Ed. 2019.
ICIQ PhD Day 2019
33
Electrocatalytic CO2 Reduction with Mn Molecular Sites into Covalent-Organic Frameworks.
G.C. Dubed,a S. S. Mondal,a F. Franco,a A. Bucci,a V. Martin-Diaconescu,a M. Ortuño,a
A. Shafir,b N. López,a J. Lloret-Fillol.a,b*
a Institut Català d’Investigació Química, The Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, Tarragona, Spain.
b Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys, 23, 08010, Barcelona, Spain.
gdubed@iciq.es
Effective large-scale CO2 conversion to fuels or value-added chemicals using
renewable energies is critical to reduce our environmental impact [1]. To this end, better understanding of the CO2 mechanism is needed to develop efficient and selective catalysts that operates in water controlling H2 evolution. Covalent Organic Frameworks (COFs) are reticular materials, which can be used to combine the advantages of the well-defined molecular catalysts and the heterogeneous ones [2]. In this work, we present the first COF based on tricarbonyl Mn units, that by π-π stacking is attached to MWCNTs form electrocatalytic electrodes active for CO2 reduction in neutral water. The activity of these catalysts was evaluated by electrochemical techniques with stability in aqueous solution. With these materials we have integrated the classical Mn(bpy)CO3Br catalyst into a heterogeneous material which clearly enhances its catalytic activity (FE~50%) at low overpotentials (~450 mV) in pure water. COF/MWCNTs/Nafion leds higher faradaic efficiency than molecular system. The encapsulation of tricarbonyl Mn active sites with a reticular covalent organic structure plays an important role by favouring the electrocatalytic CO2 reduction over competitive H2 evolution reaction. The spectroelectrochemical studies evidence the formation of five-coordinate species in the catalytic cycle for CO formation.
References [1] Sinopoli, A.; La Porte, N.T. Coord. Chem. Rev. 2018, 365, 60–74. [2] Lin S.; Yaghi, O.M. Science. 2015, 349, 1208-1213. [3] Reuillard, B.; Reisner, E. J. Am. Chem Soc. 2017, 169, 14425-14435. [4] Walsh, J.J.; Cowan, A.J. Phys. Chem. 2018, 20, 6811-6816.
ICIQ PhD Day 2019
34
Metallaphotoredox Carbamoylation of (Hetero)Aryl Bromides
N. Alandini,a L. Buzzetti,a G. Favi,a P. Melchiorre.a*
a Institut Català d’Investigació Química, The Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, Tarragona, Spain.
nalandini@iciq.es
Amides are important scaffolds found in synthetic materials, bioactive
molecules and pharmaceuticals.1 Metal-catalyzed amide formation provides an attractive alternative to classical dehydrative condensation methods.2 However, the scope and the practicality of this approach are limited by the requirement of harsh conditions, sensitive reagents and gaseous carbon monoxide. Here, we report a strategy for the carbamoylation of (hetero)aryl electrophiles based on the combination of nickel catalysis and photoredox catalysis.3 This cross-coupling approach uses readily available 1,4-dihydropyridines 1, which serve as precursors to carbamoyl radicals I, and a wide variety of (hetero)aryl bromides 2 as coupling partners. The carbamoylation protocol provides a vast array of (hetero)benzamides 3 in good to excellent efficiency with high functional-group compatibility.
References [1] Pattabiraman, V. R.; Bode, J. W. Nature 2011, 480, 471. [2] Allen, C. L.; Williams, J. M. J. Chem. Soc. Rev. 2011, 40, 3405. [3] Milligan, J. A.; Phelan, J. P.; Badir, S. O.; Molander, G. A. Angew. Chem. Int. Ed. 2019, 58, 6152.
X
Br
+
X
N
O
NH
Me Me
O N
CO2RRO2C
O
N
1 2 3
via
carbamoyl radical
NiPC
dihydropyridines aryl bromide benzamides
I
metallaphotoredox
ICIQ PhD Day 2019
35
Overriding Old Conceptions: Formal Synthesis of Indolizidine and Quinolizidine Alkaloids from Cyclic Carbonates.
À. Cristòfol,a C. Böhmer,a A. W. Kleij.a*
a Institut Català d’Investigació Química, The Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, Tarragona, Spain.
acristofol@iciq.es
The ubiquitous conception of cyclic carbonates being a protecting group of 1,2-
diols has hampered their use as reactive partners in complex synthetic routes. Recent trends, though, show a paradigmatic shift to their use as building blocks for more complex organic molecules.1,2 Herein we would like to disclose a versatile and efficient approach towards the formal synthesis of indolizidine and quinolizidine alkaloids2 from cyclic carbonates intermediates. The synthesis features a (Z)-selective palladium-catalyzed allylic alkyation of nitroalkanes as a key step.3 The synthetic strategy and versatility of the approach will be specifically discussed in this presentation.
References [1] Guo, W.; Gómez, J. E.; Cristòfol, À.; Xie, J.; Kleij, A. W. Angew. Chem. Int. Ed. 2018, 57, 13735–13747. [2] (a) Michael, J. P. Simple indolizidine and quinolizidine alkaloids. In The Alkaloids: Chemistry and Biology; Elsevier: Amsterdam, 2016; pp 1-498. (b) Michael, J. P. Nat. Prod. Rep. 2008, 25, 139–165. [3] Cristòfol, À.; Escudero-Adán, E. C.; Kleij, A. W. J. Org. Chem. 2018, 83, 9978-9990.
ICIQ PhD Day 2019
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Enantioselective Synthesis of Nicotine via an Iodine-Mediated Hofmann-Löffler Reaction
E. Del Castillo,a K. Muñiz.a,b*
a Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, Tarragona, Spain.
b Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys, 23, 08010, Barcelona, Spain.
edelcastillo@iciq.es
The Hofmann-Löffler reaction is an oxidative process of C-H amination reaction whose mechanism consists of a selective and remote intramolecular C-H functionalization followed by an intramolecular nucleophilic amination, which affords pyrrolidine cores as selective products of the overall transformation. Pyrrolidines are ubiquitous heterocycles in Nature and constitute one of the most important pharmacophoric units in the development of bioactive molecules.1 Furthermore, iodine reagents have been identified as economically and ecologically benign alternatives to transition metals.2
Our synthetic approach is based on an enantioselective construction of pirrolidine moiety through Hofmann-Löffler conditions in challenging substrates that contains a piridine ring.3
References [1] (a) O´Hagan, D. Nat. Prod. Rep. 2000, 17, 435–446. (b) Bellina, F.; Rossi, R. Tetrahedron 2006, 62 , 7213–7256. (c) Han, M. Y.; Jia, J. Y.; Wang, W. Tetrahedron Lett. 2014, 55, 784–794. [2] Martínez, C.; Muñiz, K. Angew. Chem. Int. Ed. 2015, 54, 8287–8291. [3] Del Castillo, E.; Muñiz, K. Org. Lett. 2019, 21, 705-708.
ICIQ PhD Day 2019
37
Molecular Water Oxidation Catalysts for Photo-Electrochemical Water Splitting
L. Riccardi,a C. Gimbert-Suriñach,a A. Llobet.a*
a Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, Tarragona, Spain.
lriccardi@iciq.es ludovico.riccardi@escaled-project.eu
Water is an ideal source of protons and electrons, for the fuel-production
reactions. Therefore, water oxidation [ 2 𝐻2𝑂 → 𝑂2 + 4 𝑒− + 4 𝐻+ ] is key for Artificial Photosynthesis.1
However, it is also the bottleneck of the overall process, because it requires a high thermodynamic potential and a high overpotential to overcome the kinetic barrier involved in the transfer of 4 H+ and 4e- and the formation of an O-O bond. Efficient catalysts can reduce the kinetic barrier by forming low-activation-energy intermediates, and consequently, accelerate the rates of reactions.1,2
In particular, molecular catalyst can be tuned to improve efficiency and robustness adjusting the coordination environment through ligand design. Therefore, a prior study of the mechanism and identification of active site is indispensable for enhancing the intrinsic activity.1-3
On the other hand, it is currently essential to explore applicable strategies for the heterogenization of molecular catalysts, which has proven to be an effective strategy to increase the longevity of these materials but specially to incorporate them into devices.4
The aim of this work is to develop and optimize catalysts based on earth abundant metals, and design micro-structured electrode incorporating the properly functionalized molecular catalyst in the framework of ITN eSCALED project.
References [1] Berardi, S.; Drouet, S. Francàs, L.; Gimbert-Suriñach, C.; Guttentag, M.; Richmond, C.; Stoll, T.; Llobet, A. Chem. Soc. Rev., 2014, 43, 7501-7519. [2] Matheu, R.; Garrido-Barros, P.; Gil-Sepulcre, M.; Ertem, M. Z.; Sala, X.; Gimbert-Suriñach, C.; Llobet. A. Nat. Rev. 2019. [3] Biaobiao; Z.; Sun, L. Chem. Soc. Rev., 2019, 48, 2216-2264. [4] Garrido-Barros, P.; Gimbert-Surinach, C.; Moonshiram, D.; Picón, A.; Monge, P.; Batista, V. S.; Llobet, A. J. Am. Chem. Soc. 2017, 139, 12907-12910.
ICIQ PhD Day 2019
38
Self-Assembly of Homo- and Heterodimeric Capsules Based on a Tetraspiropyran Tetraurea Calix[4]arene
G. Moncelsi,a P. Ferreira,a P. Ballester.a,b*
a Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, Tarragona, Spain.
b Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys, 23, 08010, Barcelona, Spain.
gmoncelsi@iciq.es
We report the synthesis of a tetraurea calix[4]arene featuring four appended spiropyran1 (SP) groups at its upper rim ((all-SP)-1). The tetraspiropyran tetraurea calix[4]arene self-assembles into a dimeric capsule in chloroform solution.2 Moreover, in dichloromethane solution and in the presence of 1 equiv. of trimethyl N-oxide, (all-SP)-1 quantitatively forms a heterocapsule through dimerization with a tetraurea calix[4]pyrrole.3 The photo- and acidochromic properties of the capsules are investigated by UV/Vis and 1H NMR spectroscopy techniques. Our results show that the photoisomerization of the appended SP groups of the capsules to the open-ring merocyanines (MC) occurs to a reduced extent when irradiated with 365 nm light. Consequently, the dimeric capsular assemblies are not sensitive to light irradiation in chlorinated solvents. In contrast, the addition of trifluoromethanesulfonic acid to the solution containing the capsules induces the formation of ill-defined aggregates. Most likely, the spiropyran units of the calix[4]arene component are converted into the corresponding protonated mercocyanines (MCH+). We also show that the capsular assembly/disintegration process is reversible owing to the acid/base properties of the SP/MC substituents.
References [1] Minkin, V.I. Chem. Rev. 2004, 104, 2751-2776. [2] (a) Shimizu, K. D.; Rebek, J. Proc. Natl. Acad. Sci. U. S. A. 1995, 92, 12403-12407. (b) Rebek, J. Chem. Commun. 2000, 637-643. [3] Chas, M.; Gil-Ramírez, G; Ballester, P. Org. Lett. 2011, 13, 3402-3405.
ICIQ PhD Day 2019
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Poster presentations
Session 1
Thursday, June 6th 2019, 18:30 h
Session 2
Friday, June 7th 2019, 18:00 h
ICIQ PhD Day 2019
40
Photochemical Generation of H2 and Peroxouranates
E. Petrus,a M. Segado,a N.A.F. Bandeira,a, C. Bo.a,b*
a Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, Tarragona, Spain.
b Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, Marcel·lí Domingo s/n, 43007 Tarragona, Spain.
epetrus@iciq.es
Burns’ group recently revealed a photochemical water oxidation reaction
involving uranyl nitrate which is a common nuclear waste by-product.1 In fact, it has been shown that in basic conditions and sunlight irradiation both molecular hydrogen and a peroxide complex are formed. Due to the fact that it is not a complete water oxidation, a further protonolysis must be carried out so as to regenerate the initial complexes. Even though it is not a catalytic reaction but a stoichiometric one, other groups have been attracted to explore this reactivity. Actually, Cahill’s group applied this chemistry to prepare bipiridine peroxo-bridged clusters2 and Perleppes’ group used oxime ligands3. Nevertheless, little is known on how the photochemical oxidation takes places and the hypothetically applicability of these clusters into catalysts.
Hitherto, we first proposed a ground state mechanism which lead to the formation of what we considered to be a resting state complex. From that compound we studied the excited state reactivity which ultimately led to the formation of hydrogen and uranyl peroxide.
References [1] McGrail, B.T.; Pianowski, L. S.; Burns, P.C. J. Am. Chem. Soc. 2014, 136, 4797−4800. [2] Thangavelu, S. G.; Cahill, C. L. Inorg. Chem. 2015, 54, 4208. [3] Tsantis, S. T.; Zagoraiou, E.; Savvidou, A.; Raptopoulou, C. P.; Psycharis, V.; Szyrwiel, L.; Hołyńska, M.; Perlepes, S. P. Dalton Trans. 2016, 45, 9307
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Capsular Assemblies with Polar Interior Decorate with Photochromic Units
P. Ferreira,a G. Aragay,a P. Ballester.a, b
a Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, Tarragona, Spain.
b Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys, 23, 08010, Barcelona, Spain.
pferreira@iciq.es
The design and construction of functional molecular containers based on self-assembly strategies is a topic of current interest that has already brought significant advances in the areas of molecular recognition, drug delivery or membrane transport. Molecular containers have been widely investigated over the years in order to protect and/or isolate the guest from the bulky media. Molecular encapsulation takes advantage of the intermolecular interactions established between the capsular components themselves and with the encapsulated molecule/s. Of great importance is the design of molecular containers with switchable functionalities that are addressable and responsive to an external stimulus.1 The considered photoswitchable groups experience a significant change in shape and electronic configuration (affecting their absorption spectrum) upon light irradiation.2 Incorporation of these photoswitchable moieties into the building blocks of supramolecular structures can lead to functional molecules with improved performance on its assembly/disassembly processes such as guest release.
Herein, we report the synthesis and characterization of a supramolecular capsule based on two calix[4]pyrrole units decorated with four spiropyran moieties and four urea groups. The urea groups are important for the stabilization of the capsule through a circular belt of eight unidirectionally oriented, hydrogen-bond interaction. Moreover, the included guest stablishes non-covalent interactions (H-B) with the pyrrole NH groups located at the ends of the capsule.3 Photochromic properties of supramolecular assembly were studied by UV-Vis and NMR spectroscopy.
Model of a Capsular system made by a Calix[4]pyrrole decorated with spiropyran units.
References [1] Diaz-Moscoso, A.; Arroyave, F. A.; Ballester, P. Chem. Commun. 2016, 52, 3046. [2] Yao, X., Li, T., Wang, J., Ma, X. and Tian, H. Advanced Optical Materials, 2016, 4, 1322-1349. [3] Ballester, P.; Gil-Ramirez, G. Proc. Natl. Acad. Sci. U. S. A. 2009, 106, 10455.
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DFT Study of Copper-Catalyzed Olefin Aziridination with Neutral Ligands
S. López-Resano,a M. R. Rodríguez,b M.M. Díaz-Requejo,b M.A. Pericàs,a P.J. Pérez,b F.
Maseras.a,c
a Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Avgda. Països Catalans 16, 43007 Tarragona, Spain
b Laboratorio de Catálisis Homogénea, Unidad Asociada al CSIC, Centro de Investigación en Química Sostenible (CIQSO) y Departamento de Química, Universidad de Huelva, Campus de El Carmen, 21007
Huelva, Spain cDepartment de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
slopez@iciq.es
Aziridines are important intermediates in organic synthesis for the
introduction of nitrogen substituents, and also biologically active natural products themselves. Metal-catalyzed addition of nitrenes is a powerful tool to prepare these three-membered heterocycles from alkenes.
Previous analysis on the mechanism of olefin aziridination with TpxCu and TpxAg (Tpx= tris(pyrazolyl)borate-based monoanionic ligand) has shown1,2 the involvement of singlet and triplet spin states. Recent results using the neutral tridentate ligand TTM (shown in the Figure) present a new challenge to the mechanistic interpretation. In this communication, we report our computational study on the system.
Reaction under study
References [1] Maestre, L.; Sameera, W. M. C.; Díaz-Requejo, M. M; Maseras, F; Pérez P. J. J. Am. Chem. Soc. 2013, 4, 1338-1348. [2] Llaveria, J.; Beltrán, Á.; Sameera, W. M. C.; Locati, A.; Díaz-Requejo, M. M.; Matheu, M. I.; Castillón, S; Maseras, F.; Pérez, P. J. J. Am. Chem. Soc. 2014, 14, 5342-5350.
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Catalytic Hydrogenation of CO2 to Obtain Chemical Products of Interest
M. De Fez-Febré,a J.R. Galán-Mascarós.a,b*
a Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, Tarragona, Spain.
b Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys, 23, 08010, Barcelona, Spain.
mdefez@iciq.es
CO2 is one of the main greenhouse gases produced by fossil fuels combustion.
Obtaining different chemical products by thermal hydrogenation of carbon dioxide offers a promising path to valorize carbon dioxide.1 In this sense, metal organic frameworks (MOFs) have an important role as catalysts for this reaction.
In this work, we have developed a novel, robust and microporous MOF (TAMOF-1) from copper (II) and the ligand L-2-deaza-2-(4H- 1,2,4-triazol-4-yl) histidine.2 TAMOF-1 has good properties as high permanent porosity (> 960 m2 g–1), high thermal stability (up to 200 ᵒC).
In this study, TAMOF-1 was tested for the first time as catalyst for CO2 hydrogenation reaction by pulse chemisorption equipment. The produced gases were continuously monitored by mass spectrometer obtaining formic acid as main plausible product. Based on these promising results, as next step, we will try to improve the reaction process by using a continuous flow configuration and to upgrade TAMOF-1 by blending with a Cu/ZnO-based catalyst3 that has been commonly used as one of the best catalyst for CO2 hydrogenation.
Overall crystal structure of TAMOF-1 along [111] References [1] Saeidi, S.; Amin, N. A. S.; Rahimpour, M. R. J. CO2 Util. 2014, 5, 66–81. [2] European patent application No.: EP16382480.8 (Priority date: 21/10/2016). [3] Tisseraud, C.; Comminges, C.; Belin, T.; Ahouari, H.; Soualah, A.; Pouilloux, Y.; J. Cat., 2015, 324, 41-49.
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Dynamic Covalent Capsules Based on Calix[4]pyrrole Scaffolds
C.F.M. Mirabella, a G. Aragay,a P. Ballester.a,b*
a Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, Tarragona, Spain.
b Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys, 23, 08010, Barcelona, Spain.
cmirabella@iciq.es
During the last decade, dynamic covalent chemistry has opened the way
towards an adaptive and evolutive chemistry, representing a further step towards the chemistry of complex matter. The reversibility of dynamic covalent bonds, allows the thermodynamic control of the self-assembly process of capsules and cages combining the strength of covalent bonds and the reversibility of non-covalent chemistry.
Our group has recently reported a chiral polyimine capsular assembly prepared through the template-directed synthesis using a tetraaldehyde calix[4]pyrrole scaffold and suitable diamine linkers.1
The polar interior of aryl extended calix[4]pyrroles and its bowl-like cavity, make them versatile candidates for the construction not only of supramolecular containers but also of covalent bounded capsules able to bind anionic and neutral guests mainly through the establishment of four convergent hydrogen bonds with the NHs of the calix[4]pyrrole core.2
By simple condensation between aldehyde and amine groups of two calix[4]pyrrole counterparts properly functionalized, dimeric covalent capsules have been prepared in chloroform solution (Fig. 1). The use of templates of proper dimensions (i.e. 4,4’-dipyridil-N,N’-dioxide) was necessary to afford the desired capsular assembly. The dynamic nature of these assemblies could be of interest for future applications such as controlled guest release using external stimuli (e.g. pH, competitive guest).
Molecular structures of tetra-aldehyde and tetra-amino aryl extended calix[4]pyrrole used for the assembly of the tetra-imine capsule shown as Energy minimized (MM3) structure.
References [1] Galán, A.; Escudero-Adán, E. C.; Ballester, P. Chem. Sci. 2017, 8, 7746-7750. [2] Kim, D. S.; Sessler, J. L. Chem. Soc. Rev. 2015, 44, 532-546.
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Investigation of Nickel-Catalyzed Negishi Coupling of Aryl Pivalates
C.S. Day,a R.J. Somerville,a R. Martin.a*
a Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, Tarragona, Spain.
cday@iciq.es
Nickel-catalyzed cross-coupling reactions have emerged as a dominant
methodology in challenging C-O bond activations.1 This earth abundant alternative to routinely used palladium catalysts has shown increased reactivity to otherwise inert C-O electrophiles such as pivalate esters and phenols. Although these cross-coupling reactions have received plenty of attention, they are poorly understood mechanistically. Given our current understanding of these reactions, new method development relies heavily on empirical observations. Hence, rational reaction design is difficult and new method development has been hampered.
This work will focus on exploring nickel-catalyzed Negishi cross-couplings of non-pi extended aryl pivalates. Non-pi extended systems are poorly tolerated in these cross-coupling methodologies and a deeper insight into the catalytic species may present a solution to this challenging coupling reaction.2 As such, a focus will be made on isolating previously inaccessible PCy3-ligated nickel(II) and nickel(I) catalytic species and exploring their reactivity in the realm of Negishi reactions. References
[1] Cornella, J.; Zarate, C.; Martin, R. Chem. Soc. Rev. 2014, 43, 8081−8097. [2] Somerville, R. J.; Hale, L. V. A.; Gómez-Bengoa, E.; Burés, J.; Martin, R. J. Am. Chem. Soc. 2018, 140, 8771–8780.
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Supramolecular Coordination of Pb2+ Defects in Hybrid Lead Halide Perovskite Films Using Truxene Derivatives as Lewis Base Interlayers
E. Aktas,a,b J. Jiménez-López,a,c C. Rodríguez-Seco,a,c R. Pudi,a M. A. Ortuño,a N.
López,a E. Palomares.a,d
a Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology
(BIST), Av. Països Catalans 16, Tarragona, Spain. b Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, Marcel·lí Domingo s/n, 43007
Tarragona, Spain. c Department d’Enginyeria Electrònica, Elèctrica i Automàtica, Univeristat Rovira i Virgili, Avda. Països
Catalans 26, 43007 Tarragona, Spain . d Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys, 23, 08010,
Barcelona, Spain.
eaktas@iciq.es
Truxene derivatives, due to their molecular structure and properties, are good
candidates for the passivation of defects when deposited onto hybrid lead halide perovskite thin films.1 Moreover, their semiconductor characteristics can be tailored through the modification of their chemical structure, which allows -upon light irradiation- the interfacial charge transfer between the perovskite film and the truxene molecules.2 In this work, we analysed the use of the molecules as surface passivation agents and their use in complete functional solar cells. We observed that these molecules reduce the non-radiative carrier recombination dynamics in the perovskite thin film through the supramolecular complex formation between the Truxene molecule and the Pb2+ defects at the perovskite surface. Interestingly, this supramolecular complexation neither affect the carrier recombination kinetics nor the carriers collection but induced noticeable hysteresis on the photocurrent vs voltage curves of the solar cells under sun illumination.
References [1] Ramos, F. J.; Rakstys, K.; Kazim, S.; Grätzel, M.; Nazeeruddin, M. K.; Ahmad, S. RSC Adv. 2015, 5, 53426–53432. [2] Song, D.; Wei, D.; Cui, P.; Li, M.; Duan, Z.; Wang, T.; Ji, J.; Li, Y.; Mbengue, J. M.; Li, Y.; He, Y.; Trevor, M.; Park, N.-G. J. Mater. Chem. A 2016, 4, 6091–6097.
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Z-Selective Alkylation of Alkynes via Dual Copper-Photoredox Catalysis
M. Mastandrea,a S. Cañellas,a X. Caldentey,a M.A. Pericàs.a,b*
a Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology (BIST). Av. Paisos Catalans 16, 43007, Tarragona, Spain.
b Departament de Química Inorgànica i Orgànica, Universitat de Barcelona. 08028, Barcelona, Spain.
mmastandrea@iciq.es
The direct addition of alkyl radicals to unactivated alkynes is considered to be
an often-elusive process. This is mainly due to the poor SOMO-LUMO interaction between the nucleophilic radical and the alkyne, that is reflected in the poor rate of
C−C bond formation.1 Recently, MacMillan demonstrated that -amino radicals can be captured by a nickel catalyst and coupled with an alkyne affording 1,1’-disubstituted olefins.2
In this work, we aimed at the synthesis of 1,2-disubstituted alkenes through
the addition of -amino and -oxy radicals to terminal (hetero)aromatic alkynes. We hypothesized that the aforementioned lack of reactivity could be circumvented by the transient formation of a copper acetylide complex, more prone to couple with nucleophilic radicals. As an additional practicality, we targeted the use of simple carboxylic acids as radical precursors, and the use of a benign photo-organocatalyst in contrast to metal-based photocatalysts.
To our delight, we found out the desired coupling by using a copper (II) catalyst, diamine ligand, cesium acetate as a base, and blue LED irradiation (Scheme 1). The desired alkenes were obtained in moderate to good yields (52-83% yield), obtaining the Z-alkene as the major product in most cases (60:40 to 85:15 Z:E ratio).3
Z-Selective Alkylation of Alkynes via Dual Copper-Photoredox Catalysis
References [1] Giese, B.; Lachhein, S. Angew. Chem. Int. Ed. Engl. 1982, 21, 768. [2] Till, N. A.; Smith, R. T.; MacMillan, D. W. C. J. Am. Chem. Soc. 2018, 140, 5701-5705. [3] Mastandrea, M. M.; Cañellas, S.; Caldentey, X.; Pericàs, M. A. Manuscript submitted.
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Coordinative Alignment of an Organocatalyst in a Metal-Organic Framework for the Development of Visible-Light Photoredox Strategies
L. Gutiérrez,a S. Sekhar Mondal,a N. Kandoth,a J. Lloret-Fillol.a,b*
a Institut Català d’Investigació Química, The Barcelona Institute of Science and Technology (BIST), Av. Països Catalans 16, E-43006, Tarragona (Spain).
b Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys, 23, 08010, Barcelona (Spain).
lgutierrez@iciq.es
Recently, the progress of cost-effective and less toxic organic dyes as photoredox catalysts has been encouraged in the catalysis field.1 However, these dyes are used as homogeneous catalysts that cannot be easily separated from the reaction mixture and recovered for further use. Therefore, to facilitate recovery/reuse of catalysts, new heterogeneous catalysts have been developed by immobilizing the homogeneous photocatalysts into solid-state materials including porous zeolites,2 polymers,3 and metal–organic frameworks (MOFs).4
Herein we present the coordinative alignment of an organic photocatalyst, i.e., perylene-1-carboxylic acid (P) into MOF-520, named MOF-520-P. We can directly envision a well-defined arrangement of perylene molecules inside the crystal structure of MOF-520, enhancing the understanding of its photophysical properties. Using 1% loading of MOF-520-P as a noble and redox-active metal-free organophotoredox catalyst, we perform the reductive dimerization of aromatic aldehydes and ketones under mild reaction conditions, with broad functional groups and stereoselectivity. Under light illumination with the MOF as heterogeneous catalyst, we carried out the chemical transformation in flow process for manufacturing large quantities of a product under steady-state conditions and less effort. This work provides a new approach for construction of precious metal free heterogeneous MOFs catalyst.
References [1] Romero, N.; Nicewicz, D.; Chem. Rev. 2016, 116, 10075−10166. [2] Silva, M.; Calvete, M. J. F.; Goncalves, N. P. F.; Burrows, H. D.; Sarakha, M.; Fernandes, A.; Ribeiro, M. F.; Azenha, M. E.; Perei-ra, M. M. Journal of Hazardous Materials, 2012, 233-234, 79-88. [3] (a) A. Corma and H. Garcia, Chem. Commun., 2004, 1443–1459; (b) Wang, Z. J.; Ghasimi, S.; Landfester, K.; Zhang, K. A. I. Chem. Mater. 2015, 27, 1921−1924. [4] (a) Wang, C.; Xie, Z.; deKrafft, K. E. Lin, W. J. Am. Chem. Soc. 2011, 133, 13445–13454. (b) Yu, X.; Cohen S. M., Chem. Commun. 2015, 51, 9880–9883.
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Site-Selective Ni-Catalyzed Deaminative Alkylation of Unactivated Alkenes
S.Z. Sun,a C. Romano,a R. Martin.a,b*
a Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology (BIST), Avda. Països Catalans, 16. E-43007, Tarragona, Spain.
b Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys, 23, 08010, Barcelona, Spain.
ssun@iciq.es
Alkyl amines are widely prevalent in natural products, pharmaceuticals, agrochemicals and life science molecules. Therefore, the ability to trigger a deaminative sp3 C–C bond-forming reaction would be particularly attractive for lead generation in drug discovery approaches.1 As part of our interests in Ni-catalyzed reductive coupling reactions,2 we report herein a reductive deaminative alkylation of alkyl amines with unactivated olefin feedstocks via the formation of pyridinium salts.3 This protocol is distinguished by its mild conditions, as well as by its exquisite chemo- and site-selectivity, even by using isomeric mixtures of internal olefins, enabling the targeted sp3 C–C bond-formation via chain-walking strategies.4,5 This technique has been implemented in late-stage functionalization, offering a strategic advantage to build up structural diversity from amine-containing drugs.
References [1] (a) Blakemore, D. C.; Castro, L.; Churcher, I.; Rees, D. C.; Thomas, A. W.; Wilson, D. M.; Wood, A. Nat. Chem. 2018, 10, 383. (b) Ouyang, K.; Hao, W.; Zhang, W.−X.; Xi, Z. Chem. Rev. 2015, 115, 12045. [2] (a) Sun, S.-Z.; Martin, R. Angew. Chem. Int. Ed. 2018, 57, 3622. (b) Martin-Montero, R.; Reddy Yatham, V.; Yin, H.; Davies, J.; Martin, R. Org. Lett. 2019, 21, 2947. [3] Sun, S.-Z.; Romano, C.; Martin, R. Submitted. [4] (a) Sommer, H.; Juliá-Hernández, F.; Martin, R.; Marek, I. ACS Cent. Sci. 2018, 4, 153. [5] (a) Juliá-Hernández, F.; Moragas, T.; Cornella, J.; Martin, R. Nature 2017, 545, 84. (b)
Gaydou, M.; Moragas, T.; Juliá-Hernández, F.; Martin, R. J. Am. Chem. Soc. 2017, 139, 12161. (c) Sun, S.-Z.; Borjesson, M.; Martin-Montero, R.; Martin, R. J. Am. Chem. Soc. 2018, 140, 12765.
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Nickel Catalyzed Reductive Deaminative Arylation at sp3 Carbon
Centers
R. Martin-Montero,a R. Yatham, a H. Yin, J. Davies, a R. Martin.a*
a Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology (BIST), Avda. Països Catalans, 16. E-43007, Tarragona, Spain.
b Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys, 23, 08010, Barcelona, Spain.
rmartin@iciq.es
Prompted by the ubiquity of aliphatic amines in a myriad of molecules that
display biological relevance,1 chemists have been challenged to design catalytic late-
stage functionalization techniques by sp3 C–N cleavage. As part of our ongoing interest
in cross-electrophile coupling reactions and the recent successful implementation of
pyrylium salts in cross-coupling reactions with well-defined organometallic
reagents,2,3 we present herein a methodology for forging C–C bonds via sp3 C–N
cleavage of simple aliphatic amines with aryl halides. The protocol exhibits broad
applicability with a diverse set of substitution patterns on both aryl and amine
counterparts, even in the context of late-stage functionalization of advanced synthetic
intermediates.4
References
[1] (a) Ruiz-Castillo, P.; Buchwald, S. L. Chem. Rev. 2016, 116, 12564. (b) McGrath, N. A.; Brichacek, M.; Njardarson, J. T. J. Chem. Educ. 2010, 87, 1348. [2] Serrano. E.; Martin. R.; Angew. Chem. Int. Ed. 2016, 55, 11207-11211. Börjesson. M.; Moragas. T.; Martin. R. J. Am. Chem. Soc. 2016, 138, 7504-7507. Sun. S-Z.; Martin. R. Angew. Chem. Int. Ed. 2018, 57, 3622-3625. [3] Basch. C. H.; Liao. J.; Xu. J.; Piane. J. J.; Watson. M. P. J. Am. Chem. Soc. 2017. 139. 5313-5316. [4] Martin-Montero.R; Yatham V.R.; Yin. H.; Davies. J; Martin. R. Org. Lett. 2019, 21, 2947-2951.
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Toward the Synthesis of Gold(I) Anthracene-Aminophosphine Chiral Complexes
A.H. Pérez-Jimeno,a,b A.M. Echavarren.a,b
aInstitute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology
(BIST), Avda. Països Catalans, 16. E-43007, Tarragona, Spain. b Departament de Química Analítica i Química Orgànica, Universitat Rovira i Virgili, C/Marcel·li
Domingo s/n, 43007 Tarragona (Spain).
ahperez@iciq.es
Despite the exponential growth experimented by gold(I) in homogeneous
catalysis in the last years, the study of enantioselective reactions of alkynes is still scarcely explored. Very recently, a new family of catalysts has been designed by our group in which the chiral elements are at the para position of a modified JohnPhos-type ligand.1 The new gold(I) complexes are catalytically active in a series of reactions including the intramolecular [4+2] cycloaddition of aryl alkynes with alkenes.2
Our aim is to expand the family of these JohnPhos-type ligands introducing an anthracene unit to impart rigidity to the corresponding catalysts. The new catalysts will be applied in the context of more challenging intermolecular cycloadditions and biomimetic cascade cyclizations of polyenynes.
References [1] Zuccarello, G.; Mayans, J. G.; Kirillova, M.S.; Pérez-Jimeno, A. H.; manuscript submitted. [2] (a) Nieto‐Oberhuber, C.; López, S.; Echavarren, A. M. J. Am. Chem. Soc. 2005, 127, 6178–6179. (b) Nieto‐Oberhuber, C.; Pérez‐Galán, P.; Herrero‐Gómez, E.; Lauterbach, T.; Rodríguez, C.; López, S.; Bour, C.; Rosellón, A.; Cárdenas, D. J.; Echavarren, A. M. J. Am. Chem. Soc. 2008, 130, 269–279.
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Water Oxidation with First Row Metal Complexes: Looking for the Real Catalyst
P. Pelosin,a P. Garrido-Barros,a D. Moonshiram,b S. Paria,a C. Gimbert-Suriñach,a A.
Llobet.a,*
aInstitute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology
(BIST), Avda. Països Catalans, 16. E-43007, Tarragona, Spain. b IMDEA Nanociencia Calle Faraday 9, 28049 Madrid, Spain
ppelosin@iciq.es
Artificial photosynthesis is an appealing approach for harvesting energy of the Sun and storing it in the form of chemical bonds. During this process water is oxidized to molecular oxygen, generating protons and electrons-reducing equivalents, necessary for the production of high-energy fuels, such as molecular hydrogen, CO, formic acid, etc. This approach is regarded as one of the sustainable solutions for the substitution of fossil fuels by carbon-free or carbon-neutral energy carriers.1
Since the oxidation of water is associated with the thermodynamically and kinetically demanding transfer of four electrons, four protons and the formation of an O–O bond,2 the design and synthesis of efficient water oxidation catalysts (WOCs) based on Earth-abundant elements remains a great challenge. The complex task of understanding the mechanism of water oxidation catalysis is further obstructed by low stability of the first row transition metal–based WOCs and their frequently observed Janus-faced molecular vs. oxide character under catalytic conditions.3,4 In this work a detailed analysis of the active species involved in molecular Fe complex precursors during the catalytic process will be discussed.
Janus-faced molecualr vs. oxide character of a WOC.
References
[1] Berardi S.; Drouet S.; Franca`s L.; Gimbert-Suriñach C.; Guttentag M.; Richmond C.; Stoll T. and Llobet A. Chem. Soc. Rev., 2014, 43, 7501. [2] Funes-Ardoiz I.; Garrido-Barros P.; Llobet A.; Maseras F. ACS Catal. 2017, 7, 1712. [3] Li J.; Güttinger R.; More R.; Song F.; Wan W. and Patzke G. R. Chem Soc Rev., 2017, 46, 6124. [4] Hong D.; Mandal S.; Yamada Y.; Lee Y-M.; Nam W.; Llobet A.; Fukuzumi S. Inorg. Chem.
2013, 52, 9522.
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Enantioselective Photochemical Organocascade Catalysis
G. Magagnano,a Ł. Woźniak,a P. Melchiorre.a,b*
aInstitute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology
(BIST), Avda. Països Catalans, 16. E-43007, Tarragona, Spain. bCatalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys, 23, 08010,
Barcelona, Spain.
gmagagnano@iciq.es
Cascade reactions are valuable tools for streamlining the synthesis of structurally complex chiral molecules in a single operation and from readily available substrates. Their combination with asymmetric aminocatalysis1 has led to innovative techniques for the one-step enantioselective preparation of stereochemically dense molecules.2 Recently, our laboratories found that the synthetic potential of aminocatalytic intermediates is not limited to the ground-state domain but can be expanded by exploiting their photochemical activity. For example, the photoexcitation of iminium ion can switch on novel catalytic functions that are unavailable to the ground-state reactivity. In particular, we demonstrated that excited-state chiral iminium ions act as strong SET oxidants, enabling the enantioselective β-functionalization of enals.3
Reported herein is a photochemical cascade process that combines the excited‐state and ground‐state reactivity of chiral organocatalytic intermediates. This strategy directly converts racemic cyclopropanols and α,β‐unsaturated aldehydes into stereochemically dense cyclopentanols with exquisite stereoselectivity. Mechanistic investigations have enabled elucidating the origin of the stereoconvergence, which is governed by a kinetic resolution process.4
References
[1] Barbas III, C. F. Angew. Chem. Int. Ed. 2008, 47, 42–47. [2] Enders, D.; Grondal, C.; Hüttl, M. R. M. Angew. Chem. Int. Ed. 2007, 46, 1570–1581. [3] Silvi, M.; Verrier, C.; Rey, Y. P.; Buzzetti, L.; Melchiorre, P. Nat. Chem. 2017, 9, 868–873. [4] Woźniak, Ł.; Magagnano, G.; Melchiorre, P. Angew. Chem. Int. Ed. 2018, 57, 1068–1072.
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Asymmetric Iodine(I/III)-Catalysed Diamination of Styrenes
E. Cots, a K. Muñiz.a,b* aInstitute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology
(BIST), Avda. Països Catalans, 16. E-43007, Tarragona, Spain. bCatalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys, 23, 08010,
Barcelona, Spain.
ecots@iciq.es
The recent development of chiral iodine (I/III) catalysis has enabled many
asymmetric transformations, particularly in the field of oxidation reactions1. The most notable catalyst design is based on a resorcinol core and the attachment of two lactic side chains bearing ester or amide groups. This modular nature of the mentioned structures enables a privileged catalyst synthesis as fine-tuning for the specific reaction requirement is straightforward2. This work, based on a previous iodine (III)-mediated reaction3, focuses on an enantioselective catalytic diamination of alkenes by a chiral lactate-based aryliodine within the iodine (I/III) manifold. By the use of mCPBA as terminal oxidant and under optimised conditions, the reaction proceeds under complete intermolecular reaction control to yield the diamination of terminal and internal styrenes4.
References [1] a) Haubenreisser, S.; Wöste, T. H.; Martínez, C.; Ishihara, K.; Muñiz, K. Angew. Chem. Int. Ed. 2016, 55, 413; b) Wöste, T. H.; Muñiz, K. Synthesis 2016, 48, 81. [2] Flores, A.; Cots, E.; Bergès, J.; Muñiz, K. Adv. Synth. Catal. 2019, 361, 2. [3] Röben, C.; Souto, J. A.; González, Y.; Lishchynskyi, A.; Muñiz, K. Angew. Chem. Int. Ed. 2011, 50, 9478. [4] Muñiz, K.; Barreiro, L.; Martín Romero, R.; Martínez, C. J. Am. Chem. Soc. 2017, 139, 4354.
R
I
O ON
O O
N
Cat. (20 mol%), HNMs2, mCPBA
MTBE/HFIP (3/1, v/v), -5 ºC
NMs2
NMs2
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A Stereoselective Domino Approach towards α,β-Unsaturated γ-Lactams
J. Xie,a S. Xue,a C. Qiao,a A.W. Kleij.a,b*
aInstitute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology (BIST), Avda. Països Catalans, 16. E-43007, Tarragona, Spain.
bCatalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys, 23, 08010, Barcelona, Spain.
xjianingi@iciq.es
Small nitrogen-containing heterocycles are often found in important chemicals such as natural products, pharmaceuticals and agrochemicals. Palladium-catalyzed nucleophilic amination of allylic species represents one of the most efficient ways for the construction of new C‒N bonds. Direct amination of allylic alcohols using intermolecular activation has been developed as a green and atom-economical process with water as the sole by-product. Despite notable progress in this area, direct aminolysis of allylic alcohols toward the stereoselective preparation of multisubstituted allylic amines still presents a fundamental and practical challenge. Inspired by previous research in our group concerning the stereoselective formation of (Z)-configured allylic products obtained from vinyl-substituted cyclic carbonates,[1]
herein we describe a new and attractive method for the amination of allylic alcohols under high stereocontrol (Figure 1). Key to this stereoselective transformation is the presence of a carboxylic acid acting as a directing and activating group. The isolated α,β-unsaturated lactams represent useful heterocyclic scaffolds with ample functional group diversity.[2]
References [1] For a general review: Guo, W.; Gómez, J. E.; Cristofol, A.; Xie, J.; Kleij, A. W. Angew. Chem. Int. Ed. 2018, 57, 13735-13747. [2] a) Xie, J.; Xue, S.; Escudero-Adán, E. C.; Kleij, A. W. Angew. Chem. Int. Ed. 2018, 57, 16727-16731. b) Xie J.; Qiao, C.; Belmonte, M. M.; Escudero-Adán, E. C.; Kleij, A. W. ChemSusChem 2019, DOI: 10.1002/cssc.201900433.
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Understanding Mechanochemical Reactions: A DFT Approach
B. S. Pladevall,a Feliu Maseras.a,b*
aInstitute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology (BIST), Avda. Països Catalans, 16. E-43007, Tarragona, Spain.
b Departament de Química, Universitat Autónoma de Barcelona, 08193 Bellaterra, Spain
bsanchez@iciq.es
Mechanochemical reactions are those induced by mechanical means (milling,
grinding or compression) and conducted either in solvent-free conditions or using solvent in very small amounts.1 Mechanochemistry is an emerging field with many potential applications in sustainable chemistry. Despite the growing interest on mechanochemical reactions, its underlying processes are not fully understood yet. Therefore, efforts by the scientific community to rationalize the different aspects concerning this reactivity are necessary. This investigation aims to contribute to the fundamental understanding of mechanically activated procedures through the use of computational tools.
We based our investigation on two reactions reported in previous experimental works: the synthesis of N-sulfonylguanidines2 (Figure 1, A) and a set of Diels-Alder reactions3 (Figure 1, B). Herein we demonstrate the possibility to reproduce these experimental results through the combination of computational tools and kinetic models. We conclude that when a proper media and concentration corrections are introduced, reaction mechanisms for mechanochemical reactions are comparable to those in solution.
Reactions included in the study. A, N-sulfonylguanidines synthesis and B, a set of Diels-Alder reactions.
References [1] Do, J.L.; Friščić, T. ACS Cent. Sci. 2017, 3, 13-19. [2] Tan, D.; Athanassios, C.M.; Katsenis, D.; Trukil, V.; Friščić, T. Angew. Chem. Int. Ed. 2014, 53, 9321-9324. [3] Andersen, J.M.; Mack, J. Chem. Sci. 2017, 8, 5447-5453.
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Single Atom Catalysis: The missing link between Homogeneous and Heterogeneous Catalysis
E. Fako,a* M. A. Ortuno,a N. López.a
aInstitute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology (BIST), Avda. Països Catalans, 16. E-43007, Tarragona, Spain.
efako@iciq.es
Single atom heterogeneous catalyst, SAHC, are the missing link in the Catalysis
field.1 While they share the versatility and selectivity of homogeneous catalysts they can be prepared to be as robust as heterogeneous catalysis allowing easy flow operation and high activity.2 Carbon nitride scaffolds differ from other SAHC3 and their unique intrinsic properties allow for the heterogenization of certain chemical processes which were traditionally difficult to heterogenize.2 Given the range of possibilities to tailor the composition and framework structure of carbon nitride and related materials, the findings highlight the wide technological potential of SAHCs to enable the heterogenization of challenging chemical processes.
References [1] Thomas, J. M. Nature, 2015, 525, 325. [2] (a) Chen, Z.; Vorobyeva, E.; Mitchell, S.; Fako, E.; Ortuño, M. A.; López, N.; Collins, S. M.; Midgley, P. M.; Richard, S.; Vilé, G.; Pérez-Ramírez, J. Nat. Nanotechnol., 2018, 13, 702-710. (b) Kaiser, S. K.; Lin, R.; Mitchell, S.; Fako, E.; Krumeich, F.; Hauert, R.; Safonova, O. V.; Kondratenko, V. A.; Kondratenko, E. V.; Collins, S. M.; Midgley, P. A.; López, N.; Pérez-Ramírez, J. Chem. Sci., 2019, 10, 359-369. (c) Lin, R.; Albani, D.; Fako, E.; Kaiser, S. L.; Safonova, O. V.; López, N.; Pérez-Ramírez, J. Angew. Chem. Int. Ed., 2018, 131, 514-519. [3] (a) Fako, E.; Łodziana, Z.; López, N. Catal. Sci. Technol., 2017, 7, 4285-4293. (b) Chen, Z.; Vorobyeva, E.; Mitchell, S.; Fako, E.; López, N.; Collins, S. M.; Leary, R. K.; Midgley, P. A.; Hauert, R.; Pérez-Ramírez, J. Natl. Sci. Rev., 2018, 5, 642–652 (c) Vorobyeva, E.; Chen, Z.; Mitchell, S.; Leary, R. K.; Midgley, P.; Thomas, J. M.; Hauert, R.; Fako, E.; López, N.; Pérez-Ramírez, J. J. Mater. Chem. A., 2017, 5, 16393-16403.
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Design of Multipart Catalyst with Co(II) for Photocatalytic Transformations
K. Michaliszyn,a E. S. Smirnova, a N. Kandoth,a J. Lloret-Fillol.a,b *
a Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, 43007, Tarragona (Spain) b Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys 23, 08010,
Barcelona (Spain)
kmichaliszyn@iciq.es
Supramolecular coordination complexes attract increasing attention due to
their ability to build more complex structures taking into account shapes, sizes and cavities for future applications in catalysis and molecular recognition.1 The presence of the pyrene in this complex molecules significantly enhance binding abilities through
stacking and by forming excimer upon excitation may also give information about energy transport within complex molecule scaffolds.2 Taking into account discussed above we introduce a new approach as a multipart ligand design to control the reactivity and induce enantioselectivity in light-driven H+-E umpolung catalytic reactions developed recently in our group with Co(II).3,4 The control of enantioselectivity could be achieved by the use of the second coordination sphere of the catalyst and its attaching on polycarbon surface such as nanotubes or grafene. For this purpose, the multipart ligand in addition to the metal-coordination side should possess a spacer part and polyaromatic moiety to interact with polyaromatic carbons
through stacking. With this idea in mind we developed a new synthetic route that allowed us to combine all three relevant parts of a new multipart ligand in only 5 steps. These ligands have been fully characterized in solution and solid state by polynuclear NMR spectroscopy, mass spectrometry and photophysical studies. We observed the appearance of a new band at 480 nm in the emission spectrum, that indicates the aggregation of pyrene units. In addition, 4 new cobalt (II) complexes have been synthetized and the structure of one of them has been established by X-ray analysis. The initial tests of the catalytic activity of new complexes for hydrogen evolution gave promising results.
References [1] Biz, Ch.; Ibáñez, S.; Poyatos, M.; Gusev, D.; Peris, E. Chem. Eur. J. 2017, 23, 1-7. [2] Hammarstroëm, P.; Kalman, B.; Jonsson, B.; Carlsson, U. FEBS Letters 420, 1997, 63-68. [3] Call, A.; Codol, Z; Acuña-Parés, F.; Lloret-Fillol, J. Chem. Eur. J. 2014, 20, 1–14. [4] Call, A.; Casadevall, C.; Acuña-Parés, F.; Casitas, A.; Lloret-Fillol, J. Chem. Sci. 2017 DOI: 10.1039/C7SC01276D.
ICIQ PhD Day 2019
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Exploring the Reactivity of Functionalized 7,11-dien-1-ynes in Gold(I) Catalysis
H. Armengol-Relats,a,b H. Bruss,a I. Escofet,a,b A. M. Echavarren.a,b*
a Institute of Chemical Research of Catalonia (ICIQ), Spain. b Departament de Química Analítica i Química Orgànica, Universitat Rovira i Virgili, Spain.
harmengol@iciq.es
Gold(I) catalysis has been widely applied to cycloisomerization reactions of enynes and dienynes.1 Introduction of an ether group at the propargylic position translates into a change of reactivity, giving a more complex transformation, involving an ether-migration.2 This cascade reaction has so far only been applied to 1,6-enynes and 6,10-dien-1-ynes. In this communication, we present our work on exploring the possibility to expand this methodology, by applying it to less studied cycloisomerization of 7,11-dien-1-ynes.
In an interesting example, under gold(I) catalysis, substrate 1a gave pentacyclic compound 2a, bearing an unusual trans-fused cyclopropane; while TBS-protected 1b yielded product 2b containing a cis-fused cyclopropane ring. DFT calculations provided explanation to the experimentally obtained regioselectivity.
References [1] For selected reviews: (a) Jiménez-Núñez, E.; Echavarren, A. M. Chem. Rev. 2008, 108, 3326-3350. (b) Soriano, E.; Marco-Contelles, J. Acc. Chem. Res. 2009, 42, 1026–1036. (c) Fürstner, A. Chem. Soc. Rev. 2009, 38, 3208-3221. (c) Shapiro, N. D.; Toste, F. D. Synlett 2010, 675-691. (d) Obradors, C.; Echavarren, A. M. Acc. Chem. Res. 2014, 47, 902-912. (e) Fensterbank, L.; Malacria, M. Acc. Chem. Res. 2014, 47, 953-965. (f) Dorel, R.; Echavarren, A. M. Chem. Rev. 2015, 115, 9028-9072. (g) Pflästerer, D.; Hashmi, A. S. K. Chem. Soc. Rev. 2016, 45, 1331-1367. [2] (a) Jiménez-Núñez, E.; Raducan, M.; Lauterbach, T.; Molawi, K.; Solorio, C. R.; Echavarren, A. M. Angew. Chem. Int. Ed. 2009, 48, 6152-6155. (b) Gaydou, M.; Miller, R.E.; Delpont, N.; Ceccon, J.; Echavarren, A.M. Angew. Chem. Int. Ed. 2013, 52, 6396-6399. (c) Carreras, J.; Livendahl, M.; McGonigal, P. R.; Echavarren, A. M. Angew. Chem. Int. Ed. 2014, 53, 4896-4899. (d) Calleja, P.; Pablo, Ó.; Ranieri, B.; Gaydou, M.; Pitaval, A.; Moreno, M.; Raducan, M.; Echavarren, A. M. Chem. Eur. J. 2016, 22, 13613-13618.
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