Supplementary Material (ESI) for Dalton Transactions
This journal is © The Royal Society of Chemistry 2004
The reaction of RhCp*(CH3)2(L) (L=pyridine, dmso) with GaCp* and
AlCp*: A new type of carbon-carbon bond activation reaction.
Thomas Cadenbach,a Christian Gemel,a Rochus Schmid,a Stefan Blockb and Roland A. Fischer*a
a
Anorganische Chemie II, Ruhr Universität Bochum, Universitätsstrasse 150, 44780 Bochum, Germany;
E-mail: roland.fischer@rub.de
b
Anorganische Chemie I, Ruhr Universität Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
Supplementary Material
Supplementary Material (ESI) for Dalton Transactions
This journal is © The Royal Society of Chemistry 2004
[Cp*Rh(CH3)2(dmso)] [{Cp*RhCl2}2] (0.535 g, 0.866 mmol) in THF (8 mL) was treated
with dmso (0.25 mL, 3.50 mmol) at room temperature. After stirring for 30 min, ZnMe2 (1.26
mL of a 2.0 M solution in toluene, Aldrich; 2.52 mmol) was added at -80 °C to the orange
suspension. The mixture was warmed to room temperature and stirred for 30 min, whereupon
a yellow solution formed. After hydrolysis (0.181 mL H2O, 10.08 mmol) all volatiles were
removed in vacuo and the residue extracted with toluene (3 x 5 mL). After removal of the
solvent in vacuo, the residue was then extracted with n-hexane (3 x 10 mL). The solvent
volume was reduced to ca. 10 mL and cooled at -40°C for 16 h to give the product as pale
yellow crystals. The crystals were isolated by means of canullation, washed with a small
amount of cold n-hexane and dried in vacuo. Yield: 0.422 g yellow crystals (70%).
All analytical data are in aggrement with the literature.
[Cp*Rh(CH3)2(pyridine)] [{Cp*RhCl2}2] (1.03 g, 1.66 mmol) in 15 mL THF was treated
with pyridine (2.7 mL, 33.4 mmol) at room temperature. After stirring for 30 min, ZnMe2 (2.4
mL of a 2.0 M solution in toluene, Aldrich; 4.80 mmol) was added at -80 °C to the orange
suspension. The mixture was warmed to room temperature and stirred for 30 min, whereupon
an orange solution formed. After hydrolysis (0.35 mL H2O, 19.2 mmol) all volatiles were
removed in vacuo and the residue extracted with toluene (3 x 5 mL doped with pyridine) at
0 °C. After removal of the solvent in vacuo, the residue was then extracted with n-hexane (3 x
5 mL) at 0°C. The solvent volume was reduced to ca. 8 mL and cooled at -40°C for 16 h to
give the product as orange crystals. The crystals were isolated by means of canullation,
washed with a small amount of cold n-hexane and dried in vacuo. Yield: 0.89 g orange
crystals (77%). 1H NMR δH(298 K, 250.1 MHz, C6D6): 8.21 [d, 2H], 6.69 [t, 1H], 6.29 [t,
2H], 1.55 [s, 15H], 0.75 [d, 6H, 3JRhH = 2.5 Hz]; 13C NMR δC(298 K, 62.9 MHz, C6D6): 154.5
[s], 134.7 [s], 124.3 [s], 92.3 [d, JRhC = 4.8 Hz], 9.0 [s], 3.6 [d, JRhC = 31.9 Hz]
[Cp*Rh(CpMe4GaMe3)] (1) [Cp*Rh(CH3)2(dmso)] (0.150 g, 0.433 mmol) was dissolved in
toluene (8 mL) and GaCp* (0.102 g, 0.498 mmol) was added. The solution was warmed to 60
°C and stirred for 1 h, whereupon a white precipitate was formed. After removal of all
volatiles in vacuo, the residue was washed with hexane (3 x 5 mL) and dried in vacuo. The
precipitate was redissolved in toluene (ca. 4 mL) and crystallized by slow evaporation of the
solvent. Yield: 0.141 g white crystals (69%). 1H NMR δH(298 K, 250.1 MHz, C6D6): 1.77 [s,
Supplementary Material (ESI) for Dalton Transactions
This journal is © The Royal Society of Chemistry 2004
6H], 1.34 [s, 15H], 1.06 [s, 6H], 0.15 [s, 9H];
C NMR δC(298 K, 62.9 MHz, C6D6) 117.8
13
[broad], 106.8 [d, JRhC = 8.5 Hz], 98.5 [d, JRhC = 7.9 Hz], 96.5 [d, JRhC = 7.3 Hz], 12.2 [s], 8.9
[s], 8.5 [s], 1.6 [s], -2.7[s]. Elemental Anal. Calc. for C22H36GaRh, C, 55.85; H, 7.67. Found:
C, 55.14; H, 7.29
[Cp*Rh(CpMe4AlMe3)]
The compound was prepared in situ by mixing [Cp*Rh(CH3)2(dmso)] with AlCp* (1 eq.) in
C6D6 in a screw-cap NMR sample tube. The tube was warmed to 80°C for 1h and a 1H NMR
spectrum was recorded, showing a clean spectrum of the product and dmso.
1
H NMR δH(298 K, 250.1 MHz, C6D6): 1.80 [s, 6H], 1.39 [s, 15H], 1.03 [s, 6H], -0.19 [s, 9H];
[Cp*Rh(CH3)2(GaCp*)] (2) [Cp*Rh(CH3)2(pyridine)] (0.282 g, 0.812 mmol) was dissolved
in toluene (8 mL) and GaCp* (0.183 g, 0.893 mmol) was added at 0 °C. Immediately, the
color changed from orange to red. After stirring the solution for further 10 min at 0°C, the
solvent was removed in vacuo and the residue fast extracted with n-hexane (3 x 5 mL) at 0°C.
The solvent volume was reduced to ca. 5 mL and cooled to -40°C for 16 h to give the product
as light red crystals. The crystals were isolated by means of canullation, washed with a small
amount of cold n-hexane and dried in vacuo. Yield: 0.197 g light red crystals (51 %). 1H NMR δH(298 K, 250.1 MHz, C6D6): 1.89 [s, 15H], 1.77 [s, 15H], 0.50 [d, 6H, 3JRhH = 2.7 Hz];
C NMR δC(298 K, 62.9 MHz, C6D6): 113.8, 95.1 [d, JRhC = 4.5 Hz], 10.4, 9.7, -14.3 [d, JRhC
13
= 26.8 Hz] Elemental Anal. Calc. for C22H36GaRh, C, 55.85; H, 7.67. Found: C, 55.29; H,
7.58.