Enantioselective Nucleophilic Vinylic Substitution (S N V) toward 3-Alkenyl-bisoxindoles Facilitated by C6' Steric Bulk of Cinchona Alkaloid.

A C6' bulky substituted quinine-catalyzed S N V reaction between 3-substituted oxindole and ( E )-3-(nitromethylene)-oxindole was developed. This enantioselective C( sp 3 )-C( sp 2 ) coupling furnished bisoxindole scaffolds featuring a vinyl-substituted all-carbon quaternary stereocenter with high stereoselectivities. In addition, the gram-scale synthesis and synthetic post-transformations were conducted to demonstrate the potential synthetic usefulness.