A new polymer-anchored chiral catalyst for asymmetric Michael addition reactions

[GRAPHICS] Monomer (R,R)-3 aza-3-(p-vinylbenzyl)-1,5-diphenyl-1,5-dihydroxypentane (2) when polymerized with styrene and divinylbenzene affords polymers, onto wh ich lithium and aluminum are incorporated via reaction with lithium aluminu m hydride. The resulting insoluble polymers containing chiral lithium and a luminum active centers are quite effective for asymmetric Michael addition of nitro compounds, thiols, and amines, The optimized reaction conditions y ield Michael adducts in good yield with high enantiomeric excesses.