New methods for carbon-nitrogen, carbon-sulfur, and carbon-carbon bond formations by quinone-mediated oxidation-reduction condensation using alkyl diphenylphosphinites

Abstract

A new-type of oxidation–reduction condensation using alkyl diphenylphosphinites 1 and 2,6-di-tert-butyl-1,4-benzoquinone (DBBQ) proceeded smoothly under mild and neutral conditions by using nucleophiles such as nitrogen-, carbon- or sulfur-ones whose pKa values were lower than 14. Various chiral molecules were successfully synthesized from chiral secondary or tertiary alkyl diphenylphosphinites in good to high yields with inversion of stereochemistry via SN2 displacement. Effects of the substituents of 1,4-benzoquinones and the pKa values of nucleophiles on these reactions have been investigated in detail. (Contributed by Teruaki MUKAIYAMA, M.J.A.)