抄録
A chemist-made asymmetric catalyst (“chemzyme”) for abiological transformations could be complementary to a god-made asymmetric catalyst (enzyme) for biological transformations. Thus, the development of asymmetric catalysis for abiogenetic-type reactions, carbon-carbon bond formations in particular, is the most challenging and formidable endeavor for synthetic organic chemists. Described herein is the development of the chiral titanium catalyst, prepared in the presence of molecular sieves (MS 4 A), for the enantiocontrol in carbonyl-ene reactions. The specific role of MS (zeolite), “positive” nonlinear effect, and the asymmetric catalyst-based diastereocontrol (double asymmetric induction and kinetic resolution) are also detailed.