Enantioselective Addition of Dimenthyl and Dibornyl Phosphites to Schiff Bases

摘要

Recently we described, C_N-symmetrical chiral esters of phosphorous acid, prepared from cheap optically active natural alcohols (menthol, borneol, glucofuranose, etc.,) [1-3]. These compounds are convenient asymmetric inductors in additions to C=N, C=O, and C-C bonds [4-6]. In the present work we found that replacement of the (1R, 2S, 5R)-metnthyl groups on the phosphorus atom of dialkyl phosphites by (1S)-endo-bornyl changes the configuration of the stereogenic center on the #alpha#-carbon atom of aminophosphonic acids.