ASYMMETRIC HYDROSILYLATION OF 1-ALKENES CATALYZED BY PALLADIUM-MOP

Asymmetric hydrosilylation of simple terminal alkenes (RCH=CH2) with t richlorosilane at 40 degrees C in the presence of 1x10(-3) or 1x10(-4) molar amounts of palladium catalyst prepared in situ from [PdCl-(eta( 3)-C3H5)](2) and (S)-2-diphenylphosphino-2'-methoxy-1,1'-binaphthyl (( S)-MeO-MOP) proceeded with unusual regioselectivity and with high enan tioselectivity to give high yields of 2-(trichlorosilyl)alkanes togeth er with a minor amount of 1-(trichlorosilyl) alkanes. Optically active alcohols, RCH(OH)CH3, were obtained by oxidation of the carbon-silico n bond. Regioselectivities for forming 2-silylalkanes over 1-silylalka nes and enantiomeric purities of alcohols are as follows: R=n-C4H9: 89 /11, 94% ee (R). R=n-C6H13: 93/7 95% ee (R). R=n-C10H21: 94/6, 95% ee (R). R=PhCH(2)CH(2): 81/19, 91% ee (S). R=PhCH(2)CH(2)CH(2): 80/20, 92 % ee (R). R=cyclo-C6H11: 66/34, 96% ee (R). A similar hydrosilylation of 1-alkenes, 4-pentenyl benzoate and 1,5-heptadiene gave correspondin g 2-alkanols of 90% ee and 87% ee, respectively, the ester carbonyl an d the internal double bond remaining intact.