摘要：

An insoluble chiral polymer-supported rhodium complex closely related to the soluble Rh(I)-diop complex (diop = 2,3-O-isopropylidene-2,3-dihydroxy-1,4-bis(diphenylphosphino)butane (1)) was prepared using a Merrifield resin. This insoluble system (suspended in benzene) catalyzes the asymmetric hydrogenation of α-ethylstyrene and methyl atropate with a much lower efficiency than in solution, and ethanol inhibits the catalysis. In contrast, both catalytic systems, soluble and insoluble, are very efficient for asymmetric hydrosilylation of ketones (acetophenone, methyl benzyl ketone, isobutyrophenone). For a given ketone, the optical yield strongly depends upon the silane used. Dihydrosilanes (diphenylsilane, phenylmethylsilane, α-naphthylphenylsilane) are always better than monohydrosilanes (triethylsilane, triethoxysilane, triphenylsilane). Optical yields up to 58% were obtained. In all cases, the insoluble catalyst can be filtered and easily reused.

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