Polystyrenes with chiral phosphoramide substituents as Lewis base catalysts for asymmetric addition of allyltrichlorosilane: enhancement of catalytic performance by polymer effect.
ABSTRACT In the asymmetric addition of allyltrichlorosilane to benzaldehyde, polystyrenes with chiral phosphoramide substituents as Lewis base catalysts showed up to 2.4 times better catalytic activity and 1.4 times higher enantioselectivity than the corresponding low-molecular-weight analogues.
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ABSTRACT: Sulfoxides were first introduced to the allylation of N-acylhydrazones with allyltrichlorosilanes as effective neutral coordinate-organocatalysts (NCOs). Both high diastereo- and enantioselectivity were attained when optically active chiral sulfoxides were used. Asymmetric crotylations using (Z)- and (E)-crotyltrichlorosilanes showed a high level of stereospecificity (Z --> anti and E --> syn) with high enantioselectivity.Journal of the American Chemical Society 06/2003; 125(22):6610-1. · 10.68 Impact Factor
- Angewandte Chemie International Edition 04/2003; 42(9):975-8. · 13.73 Impact Factor
- Chemical Reviews 09/2003; 103(8):2985-3012. · 41.30 Impact Factor