Supporting Information

Monodentate coordination of the normally chelating chiral diamine (R,R)-TMCDA

Ana I. Ojeda-Amador, Antonio J. Martínez-Martínez, Alan. R. Kennedy and Charles T.

O’Hara*

WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde,

Glasgow, G1 1XL (UK)

E-mail: charlie.ohara@strath.ac.uk

1

Table of Contents

EXPERIMENTAL SECTION..............................................................................................................3General Procedures...............................................................................................................................3Crystal Structure Determinations..........................................................................................................3Selected crystallographic and refinement data for 1 and 2....................................................................8Preparation of NaHMDS4.......................................................................................................................9Synthesis of [{(R,R)-TMCDA}·(NaHMDS)2]∞ 1........................................................................................9Synthesis of [κ2-{(R,R)-TMCDA}·(NaHMDS)2{κ1-(R,R)-TMCDA}] 2..........................................................10

NMR SPECTRA............................................................................................................................11Figure S1. 1H NMR spectrum of isolated crystals of 1 (400.1 MHz, [D12]-cyclohexane, 300 K)................11Figure S2. 13C{1H} NMR spectrum of isolated crystals of 1 (100.6 MHz, [D12]-cyclohexane, 300 K).........11Figure S3. 1H NMR spectrum of isolated crystals of 1 (400.1 MHz, C6D6, 300 K).....................................12Figure S4. 13C{1H} NMR spectrum of isolated crystals of 1 (100.6 MHz, C6D6, 300 K)..............................12Figure S5. 1H NMR spectrum of isolated crystals of 2 (400.1 MHz, [D12]-cyclohexane, 300 K)................13Figure S6. 13C{1H} NMR spectrum of isolated crystals of 2 (100.6 MHz, [D12]-cyclohexane, 300 K).........13Figure S7. 1H NMR spectrum of isolated crystals of 2 (400.1 MHz, C6D6, 300 K).....................................14Figure S8. 13C{1H} NMR spectrum of isolated crystals of 2 (100.6 MHz, C6D6, 300 K)..............................14Figure S9. Variable temperature 1H NMR spectra of isolated crystals of 2 (100.6 MHz, [D8]-toluene) from 300 K to 206 K showing only one type of (R,R)-TMCDA................................................................15

REFERENCES...............................................................................................................................16

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EXPERIMENTAL SECTION

General Procedures

All reactions and manipulations were performed under a protective atmosphere of dry pure

argon gas using standard Schlenk tube or glovebox techniques. n-Hexane was dried by

heating to reflux over sodium benzophenone ketyl and distilled under nitrogen prior to use.

NMR solvents were degassed and stored under argon over activated molecular sieves (4

Å) prior to use. nBuNa was prepared according to literature methods and stored in a glove

box.1 Sodium bis(trimethylsilyl)amide (NaHMDS) was prepared from nBuNa and HMDS(H)

and stored in a glove box. N,N,N',N'-(1R,2R)-tetramethylcyclohexane-1,2-diamine (R,R)-

TMCDA was prepared according to literature methods and stored under argon over

activated molecular sieves (4 Å) prior to use.2 NMR spectra were recorded on a Bruker

DPX 400 NMR spectrometer, operating at 400.1 and 100.6 MHz for 1H and 13C,

respectively. 1H and 13C{1H} NMR chemical shifts are expressed in parts per million (δ,

ppm) and referenced to the appropriate residual solvent signal. Elemental analyses of

compounds 1 and 2 were satisfactorily obtained using a Perkin Elmer 2400 elemental

analyser.

Crystal Structure Determinations

Single-crystal data were measured at 123(2) K with anon Oxford Diffraction Gemini

Diffractometer and monochromatedwith Cu-Kα radiation (λ = 1.5418 Å) for 1 and Mo-Kα

radiation (λ = 0.71073 Å) for 2. The structures were refined to convergence on F2 and

against all independent reflections by full-matrix least-squares using SHELXL programs. 3

All non-hydrogen atoms were refined anisotropically and hydrogen atoms were

geometrically placed and allowed to ride on their parent atoms. The κ1-(R,R)-TMCDA

ligand in 2 was modelled as disordered over two sites with the geometry and displacement

parameters of this group restrained to approximate typical values. Figures S1-S2 and

Table S1 contain selected metrics, crystallographic and refinement data for 1 and 2.

CCDC-XXXXXXX (1) and CCDC-XXXXXXX (2) contain the supplementary

crystallographic data for this paper. These data can be obtained free of charge from the

Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/data_request/cif.

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Figure S1. Molecular structure of [{(R,R)-TMCDA}·(NaHMDS)2]∞ 1 showing one monomeric unit of the six crystallographically independent units present infrom the asymmetric unit. Thermal ellipsoids are displayed at 35% probability and hydrogen atoms are omitted for clarity. The dashed lines illustrate Na···Me(SiMe2) interactions. Selected bond lengths (Å) and angles (º): Na(1)-N(1) 2.608(3), Na(1)-N(2) 2.527(3), Na(1)-N(3) 2.536(3), Na(1)-N(4) 2.524(3), Na(2)-N(3) 2.350(3), Na(2)-N(4) 2.367(3), Na(1)-C(22) 2.987(4), Na(1)-C(12) 3.043(4), N(4)-Na(1)-N(2) 100.50(10), N(4)-Na(1)-N(3) 95.74(9), N(2)-Na(1)-N(3) 151.55(10), N(4)-Na(1)-N(1) 149.54(10), N(2)-Na(1)-N(1) 68.70(9), N(3)-Na(1)-N(1) 106.75(10), N(4)-Na(1)-C(22) 63.84(9), N(2)-Na(1)-C(22) 101.96(12), N(3)-Na(1)-C(22) 106.15(11), N(1)-Na(1)-C(22) 89.84(10), N(4)-Na(1)-C(12) 109.06(10), N(2)-Na(1)-C(12) 89.36(10), N(3)-Na(1)-C(12) 63.16(9), N(1)-Na(1)-C(12) 99.46(10), C(22)-Na(1)-C(12) 167.43(11), N(3)-Na(2)-N(4) 105.39(10), N(3)-Na(2)-C(65) 118.32(11), N(4)-Na(2)-C(65) 136.23(11).

4

Figure S2. Section of one of the two crystallographically independent zigzag polymeric chains of [{(R,R)-TMCDA}·(NaHMDS)2]∞ 1 comprising the monomeric units [Na(1),Na(2)], [Na(3),Na(4)], [Na(5),Na(6)] and [Na(3'),Na(4')]. Thermal ellipsoids are displayed at 35% probability and hydrogen atoms are omitted for clarity. The dashed lines illustrate Na···Me(SiMe2) interactions. The symmetry operation used to generate equivalent atoms denoted with ´ is 1-x,1/2+y,1-z. Selected bond lengths (Å) and angles (º): Na(1)-N(1) 2.608(3), Na(1)-N(2) 2.527(3), Na(1)-N(3) 2.536(3), Na(1)-N(4) 2.524(3), Na(2)-N(3) 2.350(3), Na(2)-N(4) 2.367(3), Na(1)-C(22) 2.987(4), Na(1)-C(12) 3.043(4), Na(2)-C(65) 2.818(4), Na(3)-N(5) 2.605(3), Na(3)-N(6) 2.522(3), Na(3)-N(7) 2.556(3), Na(3)-N(8) 2.537(3), Na(4)-N(7) 2.351(3), Na(4)-N(8) 2.341(3), Na(3)-C(33) 3.083(4), Na(4) C(11) 2.763(4), Na(5)-N(9) 2.686(3), Na(5)-N(10) 2.528(3), Na(5)-N(11) 2.508(3), Na(5)-N(12) 2.609(3), Na(6)-N(11) 2.378(3), Na(6)-N(12) 2.357(3), Na(5)-C(64) 2.983(4), Na(5)-C(56) 3.047(4), Na(6)-C(43') 2.816(3), Na(6)-C(60) 2.958(4), N(4)-Na(1)-N(2) 100.50(10), N(4)-Na(1)-N(3) 95.74(9), N(2)-Na(1)-N(3) 151.55(10), N(4)-Na(1)-N(1) 149.54(10), N(2)-Na(1)-N(1) 68.70(9), N(3)-Na(1)-N(1) 106.75(10), N(4)-Na(1)-C(22) 63.84(9), N(2)-Na(1)-C(22) 101.96(12), N(3)-Na(1)-C(22) 106.15(11), N(1)-Na(1)-C(22) 89.84(10), N(4)-Na(1)-C(12) 109.06(10), N(2)-Na(1)-C(12) 89.36(10), N(3)-Na(1)-C(12) 63.16(9), N(1)-Na(1)-C(12) 99.46(10), C(22)-Na(1)-C(12) 167.43(11), N(3)-Na(2)-N(4) 105.39(10), N(3)-Na(2)-C(65) 118.32(11), N(4)-Na(2)-C(65) 136.23(11), N(6)-Na(3)-N(8) 149.46(10), N(6)-Na(3)-N(7) 100.99(10), N(8)-Na(3)-N(7) 95.86(9), N(6)-Na(3)-N(5) 68.67(10), N(8)-Na(3)-N(5) 108.12(10), N(7)-Na(3)-N(5) 147.64(10), N(6)-Na(3)-C(33) 102.37(11), N(8)-Na(3)-C(33) 108.01(11), N(7)-Na(3)-C(33) 62.19(9), N(5)-Na(3)-C(33) 89.32(10), N(6)-Na(3)-C(29) 27.59(9), N(8)-Na(3)-C(29) 172.24(11), N(7)-Na(3)-C(29) 80.56(10), N(5)-Na(3)-C(29) 77.87(10), C(33)-Na(3)-C(29) 76.51(11), Na(4)-Na(3)-C(29) 128.13(8), N(8)-Na(4)-N(7) 107.39(10), N(8)-Na(4)-C(39) 63.81(9), N(7)-Na(4)-C(39) 109.68(11), N(8)-Na(4)-C(11) 119.00(11), N(7)-Na(4)-C(11) 133.41(11), C(11)-Na(4)-C(39) 88.14(11), N(11)-Na(5)-N(10) 149.22(10), N(11)-Na(5)-N(12) 94.95(9), N(10)-Na(5)-N(12) 102.64(10), N(11)-Na(5)-N(9) 107.20(10), N(10)-Na(5)-N(9) 66.13(10), N(12)-Na(5)-N(9) 152.13(10), N(11)-Na(5)-C(64) 100.66(10), N(10)-Na(5)-C(64) 109.79(11), N(12)-Na(5)-C(64) 62.93(9), N(9)-Na(5)-C(64) 95.78(10), N(11)-Na(5)-C(56) 62.94(10), N(10)-Na(5)-C(56) 88.70(11), N(12)-Na(5)-C(56) 101.36(11), N(9)-Na(5)-C(56) 103.67(12), C(64)-Na(5)-C(56) 157.47(12), N(11)-Na(5)-C(54) 177.39(11), N(10)-Na(5)-C(54) 28.28(9), N(12)-Na(5)-C(54) 85.90(10), N(9)-Na(5)-C(54) 72.74(11), C(64)-Na(5)-C(54) 81.93(11), C(56)-Na(5)-C(54) 114.48(11), N(11)-Na(5)-C(52) 83.50(10), N(10)-Na(5)-C(52) 79.72(10), N(12)-Na(5)-C(52) 177.28(11), N(9)-Na(5)-C(52) 27.88(10), C(64)-Na(5)-C(52) 115.10(12), C(56)-Na(5)-C(52) 79.95(13), C(54)-Na(5)-C(52) 95.74(11), N(12)-Na(6)-N(11) 105.57(10), N(12)-Na(6)-C(43') 115.92(11), N(11)-Na(6)-C(43') 137.39(11), N(12)-Na(6)-C(60) 121.72(12), N(11)-Na(6)-C(60) 66.28(10), C(43')-Na(6)-C(60) 97.82(11).

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Figure S3. Section of one of the two crystallographically independent zigzag polymeric chains of [{(R,R)-TMCDA}·(NaHMDS)2]∞ 1 comprising the monomeric units [Na(7),Na(8)], [Na(9),Na(10)], [Na(11),Na(12)] and [Na(11''),Na(12'')]. Thermal ellipsoids are displayed at 35% probability and hydrogen atoms are omitted for clarity. The dashed lines illustrate Na···Me(SiMe 2) interactions. The symmetry operation used to generate equivalent atoms denoted with ´ is -x,y-1/2,1-z. Selected bond lengths (Å) and angles (º): Na(7)-N(13) 2.594(3), Na(7)-N(14) 2.582(3), Na(7)-N(15) 2.560(3), Na(7)-N(16) 2.531(3), Na(8)-N(15) 2.344(3), Na(8)-N(16) 2.352(3), Na(7)-C(80) 3.068(4), Na(7)-C(73) 3.068(4), Na(7)-C(76) 3.088(5), Na(7)-C(85) 3.094(4), Na(8)-C(100) 2.798(3), Na(8)-C(88) 3.038(4), Na(8)-C(77) 3.072(4), Na(9)-N(17) 2.658(3), Na(9)-N(18) 2.565(3), Na(9)-N(19) 2.638(3), Na(9)-N(20) 2.486(3), Na(10)-N(19) 2.364(3), Na(10)-N(20) 2.376(3), Na(9)-C(97) 2.929(4), Na(9)-C(99) 2.969(3), Na(10)-C(127'') 2.901(3), Na(10)-C(106) 2.948(4), Na(11)-N(23) 2.517(3), Na(11)-N(22) 2.580(3), Na(11)-N(24) 2.611(3), Na(11)-N(21) 2.628(3), Na(12)-N(24) 2.362(3), Na(12)-N(23) 2.377(3), Na(11)-C(120) 2.980(4), Na(11)-C(128) 3.068(4), Na(12)-C(82) 2.835(4), Na(12)-C(123) 2.922(4), N(16)-Na(7)-N(15) 95.28(9) N(16)-Na(7)-N(14) 99.40(10), N(15)-Na(7)-N(14) 161.84(10), N(16)-Na(7)-N(13) 158.68(10), N(15)-Na(7)-N(13) 101.30(9), N(14)-Na(7)-N(13) 67.40(10), N(16)-Na(7)-C(80) 111.11(10), N(15)-Na(7)-C(80) 62.68(9), N(14)-Na(7)-C(80) 101.74(10), N(13)-Na(7)-C(80) 88.56(10), N(16)-Na(7)-C(73) 135.60(11), N(15)-Na(7)-C(73) 99.14(10), N(14)-Na(7)-C(73) 77.65(10), N(13)-Na(7)-C(73) 28.27(10), C(80)-Na(7)-C(73) 112.85(11), N(16)-Na(7)-C(76) 98.65(12), N(15)-Na(7)-C(76) 138.55(11), N(14)-Na(7)-C(76) 28.08(10), N(13)-Na(7)-C(76) 77.63(12), C(80)-Na(7)-C(76) 75.88(11), C(73)-Na(7)-C(76) 97.64(12), N(16)-Na(7)-C(85) 62.27(9), N(15)-Na(7)-C(85) 107.61(11), N(14)-Na(7)-C(85) 88.76(11), N(13)-Na(7)-C(85) 99.58(10), C(80)-Na(7)-C(85) 168.64(11), C(73)-Na(7)-C(85) 73.35(11), C(76)-Na(7)-C(85) 113.45(12), N(15)-Na(8)-N(16) 106.49(10), N(15)-Na(8)-C(100) 118.73(11), N(16)-Na(8)-C(100) 134.77(11), N(15)-Na(8)-C(88) 111.69(11), N(16)-Na(8)-C(88) 64.86(11), C(100)-Na(8)-C(88) 96.12(12), N(15)-Na(8)-C(77) 64.38(10), N(16)-Na(8)-C(77) 110.54(11), C(100)-Na(8)-C(77) 90.43(11), C(88)-Na(8)-C(77) 173.43(13), N(20)-Na(9)-N(18) 160.94(10), N(20)-Na(9)-N(19) 94.41(9), N(18)-Na(9)-N(19) 95.65(9), N(20)-Na(9)-N(17) 106.14(10), N(18)-Na(9)-N(17) 66.10(9), N(19)-Na(9)-N(17) 158.94(10), N(20)-Na(9)-C(97) 134.35(10), N(18)-Na(9)-C(97) 30.05(9), N(19)-Na(9)-C(97) 89.10(10), N(17)-Na(9)-C(97) 79.94(10), N(20)-Na(9)-C(99) 104.83(10), N(18)-Na(9)-C(99) 94.16(10), N(19)-Na(9)-C(99) 63.04(9), N(17)-Na(9)-C(99) 106.11(10), C(97)-Na(9)-C(99) 117.00(11), N(19)-Na(10)-N(20) 105.00(10), N(19)-Na(10)-C(127'') 114.38(10), N(20)-Na(10)-C(127'') 140.53(10), N(19)-Na(10)-C(106) 119.49(11), N(20)-Na(10)-C(106) 66.55(9), C(127'')-Na(10)-C(106) 95.09(11), N(23)-Na(11)-N(22) 160.52(10), N(23)-Na(11)-N(24) 94.72(9), N(22)-Na(11)-N(24) 98.37(9), N(23)-Na(11)-N(21) 103.15(10), N(22)-Na(11)-N(21) 65.98(9), N(24)-Na(11)-N(21) 161.22(9), N(23)-Na(11)-C(120) 136.49(10), N(22)-Na(11)-C(120) 29.40(9), N(24)-Na(11)-C(120) 91.30(10), N(21)-Na(11)-C(120) 79.76(10), N(23)-Na(11)-C(128) 105.04(10), N(22)-Na(11)-C(128) 93.87(10), N(24)-Na(11)-C(128) 61.79(9), N(21)-Na(11)-C(128) 107.19(10), C(120)-Na(11)-C(128) 115.61(11), N(24)-Na(12)-N(23) 105.54(10), N(24)-Na(12)-C(82) 117.63(11), N(23)-Na(12)-C(82) 136.05(10), N(24)-Na(12)-C(123)

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121.80(12), N(23)-Na(12)-C(123) 66.90(10),C(82)-Na(12)-C(123) 95.20(11).

Figure S4. Molecular structure of [{κ2-(R,R)-TMCDA}·(NaHMDS)2{κ1-(R,R)-TMCDA}] 2. Hydrogen atoms and one disordered component of the mono-dentate (R,R)-TMCDA ligand are omitted for simplicity. Thermal ellipsoids are displayed at 35% probability. Selected bond lengths (Å) and angles (º): Na(1)-N(6) 2.501(2), Na(1)-N(5) 2.537(2), Na(1)-N(4) 2.578(2), Na(1)-N(3) 2.665(2), Na(1)-C(27) 2.968(3), Na(1)-C(24) 2.976(3), Na(2)-N(5) 2.416(2), Na(2)-N(6) 2.444(2), N(6)-Na(1)-N(5) 95.87(7), N(6)-Na(1)-N(4) 102.03(7), N(5)-Na(1)-N(4) 151.05(8), N(6)-Na(1)-N(3) 146.63(8), N(5)-Na(1)-N(3) 108.27(7), N(4)-Na(1)-N(3) 66.90(6), N(6)-Na(1)-C(27) 65.05(8), N(5)-Na(1)-C(27) 107.18(8), N(4)-Na(1)-C(27) 100.99(8), N(3)-Na(1)-C(27) 85.57(8), N(6)-Na(1)-C(24) 105.87(8), N(5)-Na(1)-C(24) 64.21(7), N(4)-Na(1)-C(24) 88.89(8), N(3)-Na(1)-C(24) 105.28(8), C(27)-Na(1)-C(24) 167.65(9), N(5)-Na(2)-N(6) 100.63(7).

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Selected crystallographic and refinement data for 1 and 2

Table S1. Selected crystallographic and refinement data for 1 and 2.

1 2

Formula C22H58N4Na2Si4 C32H80N6Na2Si4Fw 537.06 707.36Cryst. System Monoclinic OrthorhombicSpace Group P21 P212121

Wavelength/Å 1.541840 0.71073a/Å 16.9445(2) 11.6278(4)b/Å 37.8065(3) 11.8670(5)c/Å 17.8856(2) 32.841(2)α/° 90 90β/° 116.408(2) 90γ/° 90 90Volume/Å3 10262.1(2) 4531.6(4)Z 12 4Temp./K 123(2) 123(2)Refls. Collect. 101381 258542θmax 146.36 60.95Refls. Ind. 39530 11578Refls. Obs. 37174 9541Rint 0.0439 0.0349Goodness of fit 1.014 1.0256R[F2>2σ], F 0.0410 0.0431

Rw (all data), F2 0.1059 0.09278

Flack 0.013(13) -0.03(4)

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Preparation of NaHMDS4

nBuNa (1.6 g, 20 mmol) was suspended in n-hexane (40 mL), stirred for 10 min and

HMDS(H) (4.2 mL, 20 mmol) was then added at room temperature. The reaction

mixture was stirred for 2 h to give a white suspension. The solvent was partially

removed under vacuum (c.a. 20 mL) and the suspension was filtered. The solid was

washed with n-hexane (3 x 5 mL) and dried under vacuum for 20 minutes to give

NaHMDS as a white solid. The product was stored under the inert atmosphere of a

glove box.

Synthesis of [{(R,R)-TMCDA}·(NaHMDS)2]∞ 1

Freshly prepared NaHMDS (440 mg, 2.4 mmol) was suspended in n-hexane (10 mL)

and stirred for 5 min at room temperature. (R,R)-TMCDA (22.8 μL, 1.2 mmol) was

then added and the reaction mixture was stirred for 15 min to give a slightly cloudy

pale orange solution. The reaction mixture was filtered via cannula and the solvent

was partially removed under vacuum (c.a. 3 mL). Suitable crystals of 1 for an X-ray

diffraction study were obtained at -33°C after 24 hours. The colourless crystalline

material was filtered, washed with cold n-hexane (3 x 5 mL) and dried under vacuum

for 15 min. Yield: 230 mg, 0.43 mmol, 36% (based on (R,R)-TMCDA consumption).

Alternatively, 1 can be prepared by reacting NaHMDS (367 mg, 2 mmol) with (R,R)-

TMCDA (38 μL, 2 mmol) at room temperature in n-hexane (10 mL) for 1 h. The

reaction mixture was filtered via cannula to give a pale orange solution. The solvent

was partially removed under vacuum (c.a. 3 mL) and crystals were obtained at -33°C

after 48 h. X-ray crystallographic and NMR spectroscopic studies proved that this

crystalline material resembles 1. The colourless crystalline material was filtered,

washed with n-hexane (3 x 5 mL) and dried under vacuum for 20 min. Yield: 290 mg,

0.54 mmol, 27% (based on (R,R)-TMCDA consumption). 1H NMR (400.1 MHz, C6D6,

300 K): δ 0.27 (s, 36 H, SiMe3), 0.74 (m, 4 H, β/γ-CH2, (R,R)-TMCDA), 1.46 (m, 4 H,

β/γ-CH2, (R,R)-TMCDA), 1.90 (m, 2 H, α-CH, (R,R)-TMCDA), 2.01 (s, 12 H, Me,

(R,R)-TMCDA). 13C{1H} NMR (100.6 MHz, C6D6, 300 K): δ 7.1 (SiMe3), 22.1 (β/γ-CH2,

(R,R)-TMCDA), 25.5 (β/γ-CH2, (R,R)-TMCDA), 40.4 (Me, (R,R)-TMCDA), 63.9 (α-

CH, (R,R)-TMCDA). Anal. Calcd (Found) for C22H58N4Na2Si4: C, 49.20 (49.14); H,

10.89 (10.69); N, 10.43% (10.17%).

9

Synthesis of [κ2-{(R,R)-TMCDA}·(NaHMDS)2{κ1-(R,R)-TMCDA}] 2

Freshly prepared NaHMDS (551 mg, 3 mmol) was suspended in n-hexane (10 mL)

and stirred for 5 min at room temperature. (R,R)-TMCDA (1.14 mL, 6 mmol) was

then added and the reaction mixture was stirred for 15 min. The resulting pale

orange solution was filtered via cannula and the solvent was partially removed under

vacuum (c.a. 3 mL). Suitable crystals of 2 for an X-ray diffraction study were

obtained at -33 °C after 24 hours. The colourless crystalline material was filtered,

washed with cool n-hexane (3 x 5 mL) and dried under vacuum for 15 min. Yield:

420 mg, 0.59 mmol, 40% (based on (R,R)-TMCDA consumption). 1H NMR (400.1

MHz, C6D6, 300 K): δ 0.30 (s, 18 H, SiMe3), 0.80 (m, 4 H, β/γ-CH2, (R,R)-TMCDA),

1.51 (m, 4 H, β/γ-CH2, (R,R)-TMCDA), 1.99 (m, 2 H, α-CH, (R,R)-TMCDA), 2.06 (s,

12 H, Me, (R,R)-TMCDA). 13C{1H} NMR (100.6 MHz, C6D6, 300 K): δ 7.2 (SiMe3),

23.2 (β/γ-CH2, (R,R)-TMCDA), 25.6 (β/γ-CH2, (R,R)-TMCDA), 40.4 (α-CH, (R,R)-

TMCDA), 64.0 (Me, (R,R)-TMCDA). Anal. Calcd (Found) for C32H80N6Na2Si4: C,

54.34 (54.48); H, 11.40 (11.06); N, 11.88% (11.88%).

10

NMR SPECTRA

Figure S1. 1H NMR spectrum of isolated crystals of 1 (400.1 MHz, [D12]-cyclohexane, 300 K).

Figure S2. 13C{1H} NMR spectrum of isolated crystals of 1 (100.6 MHz, [D12]-cyclohexane, 300 K).

11

Figure S3. 1H NMR spectrum of isolated crystals of 1 (400.1 MHz, C6D6, 300 K).

Figure S4. 13C{1H} NMR spectrum of isolated crystals of 1 (100.6 MHz, C6D6, 300 K).

12

Figure S5. 1H NMR spectrum of isolated crystals of 2 (400.1 MHz, [D12]-cyclohexane, 300 K).

Figure S6. 13C{1H} NMR spectrum of isolated crystals of 2 (100.6 MHz, [D12]-cyclohexane, 300 K).

13

Figure S7. 1H NMR spectrum of isolated crystals of 2 (400.1 MHz, C6D6, 300 K).

Figure S8. 13C{1H} NMR spectrum of isolated crystals of 2 (100.6 MHz, C6D6, 300 K).

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Figure S9. Variable temperature 1H NMR spectra of isolated crystals of 2 (100.6 MHz, [D8]-toluene) from 300 K to 206 K showing only one type of (R,R)-TMCDA.

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300 K

263 K

233 K

206 K

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J.-C. Kizirian, N. Cabello, L. Pinchard, J.-C. Caille and A. Alexakis, Tetrahedron, 2005, 61, 8939.

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Driess, H. Pritzkow, M. Skipinski and U. Winkler, Organometallics, 1997, 16, 5108-5112; (c) J. Knizek, I. Krossing, H. Nöth, H. Schwenk and T. Seifert, Chem. Ber./Recl., 1997, 130, 1053-1062.

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