Regioselectivity Obtained by Using Non-covalent Interactions

2017/4/15

M1 Kentaro Sakai

1. Introduction

2. Regioselective Reaction Using the Ion-pair Interaction

3. Regioselective Reaction Using the Hydrogen Bonding

4. Summary

2/42Today’s Topics

1. Introduction

Example of Non-covalent Interactions4/42

5/42Example of Enantioselective Reaction Using Non-covalent Interaction

6/42Proposed Catalytic Cycle

7/42①The Presence of Innate Reactivity

8/42②The Number of Choices

9/42Summary of Section 1

2. Regioselective Catalyst Using the Ion-pair Interaction

Ion-pair Interaction11/42

Regioselective Reaction Using Ion-pair Interaction12/42

Importance of the Presence of Cation Charge 13/42

Importance of the Presence of Anion Charge 14/42

Importance of Substrate and Ligand Interaction 15/42

Assumed Reaction Mechanism16/42

Substrate Scope 1 (disubstituted)17/42

Substrate Scope 2 (monosubstituted)18/42

Application? Limitation?19/42

A Solution of the Problem20/42

21/42Summary of Section 2

3. Regioselective Catalyst Using the Hydrogen Bonding

Regioselective Reactions Using Hydrogen Bonding23/42

Regioselective Acylation of Polyol24/42

Catalyst-controled regioselectivity was observed.

The Side-chain Effect25/42

Importance of Free NH of Catalyst26/42

Importance of Free OH of Substrate27/42

6-OH group of the substrate was important for regioselectivity.

Important Sites for Regioselectivity Expression28/42

Solvent Effect 29/42

Polar solvent decreased yields and regioselectivity.

No Effect of Additives30/42

The presence of alcohol didn’t inhibit the selective acylation.

Proposed Reaction Mechanism31/42

Various Acyl Donor32/42

Acylation of Other Structures33/42

Chemoselective Acylation of 1,n-diol (1)34/42

It was difficult to suppress the double acylation in the previous method.

Chemoselective Acylation of 1,n-diol (2)35/42

Acylation with catalyst A avoided double functionalization.

Solvent Effect on Chemoselectivity36/42

Hydrogen bonds may be involved in this reaction.

The Effect of Chain Length37/42

Long chain decreased selectivity.

Proposed Mechanism of the Phenomenon38/42

My Idea: Regioselective Acylation of 1,n-diol ?39/42

May such regioselective reaction be possible?

40/42Summary of Section 3

4. Summary

42/42Summary of Today’s Literature Seminar