Chelation control in the addition of homophthalic anhydride to α-alkoxy imines. Pancratistatin model studies

Article abstract of DOI:10.1016/S0040-4039(00)94368-5

Diastereoselectivity in the addition of homophthalic anhydride to the α-alkoxy imine (S)-5 can be increased dramatically (to> 90%) with addition of Lewis acids. This methodology has been applied to the synthesis of a model compound (12) which contains four asymmetric centers with the same relative stereochemistry as pancratistatin (1).