Improved asymmetric [S.sub.N]Ar reaction of [beta]-dicarbony compounds catalyzed by quaternary ammonium salts derived from cinchona alkaloids

The scope and limitation of the asymmetric nucleophilic aromatic substitution reaction of [alpha]-substituted 1,3-dicarbonyl compounds and activated aromatic systems catalyzed by N-benzyl-O-benzoylcinchoninium or cinchonidinium salts are presented. Various 1,3-dicarbonyl compounds and activated aromatic systems are evaluated for the aromatic nucleophilic substitution reaction, and it was found that the yield and enantioselectivity are very dependent on the substrate and reagent.