Twelve chiral copper(Ⅱ)Schiff base complexes, derived from (R)(+)2amino1,1diaryl1propanol with substituted salicylaldehydes, were examined as a catalyst for asymmetric cyclopropanation of styrene with ethyl diazoacetate. It was found that the substituents at 3and 5positions of salicylaldehyde in the ligands had great effects on catalytic activity and enantioselectivity of the catalyst. The complex with strong electronwithdrawing group (NO2) at 5position and the smallest stereohinder (H) at 3position of salicylaldehyde showed highly catalytic activity and enantioselectivity, up toee=874% fortransandee=828% forcisisomers respectively, and the ratio 39/61 ofcistotransisomers was obtained at 40 ℃ with 1,2dichloroethane as solvent.……
