Development of a tandem base-catalyzed, triphenylphosphine-mediated disulfide reduction-Michael addition

A tandem disulfide reduction-Michael addition was developed using both free and polymer-bound triphenylphosphine as the reducing agent. The procedure was applied to intermolecular systems for the synthesis of arylsulfanyl- and alkylsulfanyl- sub sti tuted propanoates and related ketones, and to an intramolecular system for the synthesis of a benzothiazepinone derivative.