Gasphase basicities of α-trimethylsilylstyrenes have been determined by measuring proton transfer equilibrium constants. Basicity of α-trimethylsilylstyrene was found to be comparable to that of α-alkylstyrene, suggesting that α-trimethylsilyl group as well as α-alkyl group stabilizes a carbeniumion.
Asymmetric hydrogenation of 1-silyl-1-substituted alkenes for preparation of optically active silanes
作者:Dan-Dan Ma、Peiming Gu、Rui Li
DOI:10.1016/j.tetlet.2016.11.017
日期:2016.12
Asymmetrichydrogenation of 1-silyl-1-substituted alkenes has been explored, producing eight optically active silanes with good to excellent enantioselectivity (66–99% ee) and yield (74–99%). The reaction was efficiently catalyzed by the cationic N,P-Ir complexes, and the polar solvents were found to be essential for the stereocontrol of the conversion.