3-Oxo-2-(triphenyl-γ~5-phosphanylidene)-4-(phenylsulfmyl)butanenitrile: Ah Efficient Reagent for α-Keto (Cyanomethylene)triphenylphosphoranes from Alkyl Bromides

摘要

Due to the presence in biologically important natural products as the highly electrophilic structural unit and incorporation into many clinically active synthetic peptides as the ketone pharmacophore in recent years, α-keto amide/ester units have been active research topics for synthetic and medicinal chemists. Wasserman et al. reported an elegant synthetic approach to these units utilizing cyanophosphorane ylide chemistry under very mild conditions in a convergent manner (Scheme 1).