Enantioselective addition of diphenyl phosphonate to ketimines derived from isatins catalyzed by binaphthyl-modified organocatalysts

Abstract

Chiral binaphthyl-modified squaramide-catalyzed enantioselective addition of diphenyl phosphonate to ketimines derived from isatins has been achieved. This method affords practical and efficient access to chiral 3-amino-3-phosphonyl-substituted oxindole derivatives in high yields with excellent enantioselectivities (up to 99% ee).

Keywords

• 3-amino-3-phosphonyl-substituted oxindole
• α-aminophosphonates
• bifunctional organocatalyst
• ketimines
• organocatalysis
• squaramide