THE DEVELOPMENT AND APPLICATION OF A NEW CLASS OF MONODENTATE OPTICALLY-ACTIVE PHOSPHINES (MOPS) - ASYMMETRIC HYDROSILYLATION OF OLEFINS CATALYZED BY PALLADIUM-MOP COMPLEXES

Axially chiral monodentate optically active phosphines 1, (S)-2-(diphenylphosphino)-2'-methoxy-1,1'-binaphthyl (MOP, 1 b) and its analogs were prepared. Reaction of simple terminal alkenes 6, (RCH=CH2. R = n-C4H9, n-C6H13, n-C10H21, PhCH2CH2, cyclo-C6H11) with trichlorosilane at 40-degrees-C in the presence of 0.1 or 0.01 mol % of palladium catalyst, prepared in situ from [PdCl(pi-C3H5)]2 and (S)-1 b, proceeded with unusual regioselectivity (up to 94%) and with high enantioselectivity to give high yields of 2-(trichlorosilyl) alkanes 7 a together with a minor amount of 1-(trichlorosilyl) alkanes 7 b. Oxidation of the carbon-silicon bond gave optically active alcohols 9 (RCH(OH)CH3), with the enantiomeric purity ranging between 94% and 97% ee. The high enantioselectivity was also observed in the enantioposition-selective hydrosilylation of norbornene (19) and related meso bicyclic olefins catalyzed by the MOP/palladium, which gave exo-2-norbornanol (21 and the related alcohols with up to 96% ee.