Access to Stable Quaternary Phosphiranium Salts by P-Alkylation and P-Arylation of Phosphiranes

Abstract : We report the preparation of phosphiranium salts by quaternarization of phosphiranes, a class of sensitive, highly strained and poorly nucleophilic cyclic phosphines. High yielding introduction of a varied set of alkyl groups including methylene ester arms was accomplished under mild conditions. A Cu-catalyzed electrophilic arylation of phosphiranes using diaryl iodonium reagents was also achieved to yield unprecedented P,P diaryl phosphiraniums salts with good efficiency.