Direct Substitution of the Hydroxy Group in Alcohols with Silyl Nucleophiles Catalyzed by Indium Trichloride
作者:Makoto Yasuda、Takahiro Saito、Masako Ueba、Akio Baba
DOI:10.1002/anie.200353121
日期:2004.3.5
Direct Coupling Reaction between Alcohols and Silyl Compounds: Enhancement of Lewis Acidity of Me<sub>3</sub>SiBr Using InCl<sub>3</sub>
作者:Takahiro Saito、Yoshihiro Nishimoto、Makoto Yasuda、Akio Baba
DOI:10.1021/jo061512k
日期:2006.10.1
The combination of InCl3 and Me3SiBr provided an enhanced Lewis acid system that can be used to promote a wide range of direct coupling reactions between alcohols and silyl nucleophiles in non-halogenated solvents, such as hexane or MeCN. The enhanced Lewis acidity of this system was measured by the C-13 NMR in terms of the coordination to an alcohol. Moreover, the interaction between Me3SiBr and the In(III) species was revealed by Si-29 NMR spectral analysis. Highly chemoselective allylations toward a hydroxyl moiety over ketone and acetoxy ones have been demonstrated.
Rhodium-Catalyzed Allylation of Benzyl Acetates with Allylsilanes
allylation product in the presence of a catalytic amount of the (cyclooctadiene)rhodium(I) chloride dimer [Rh(cod)Cl]2}, sodium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate (NaBARF), and triphenyl phosphite [P(OPh)3] in refluxing 1,2-dichloroethane. Primary, secondary and tertiary benzyl acetates could be used for the reaction. Moreover, allylation of gem-benzyl acetate was possible with [Rh(cod)Cl]2, NaBARF