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 pK_a 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 S_N2 displacement. Effects of the substituents of 1,4-benzoquinones and the pK_a values of nucleophiles on these reactions have been investigated in detail.


(Contributed by Teruaki MUKAIYAMA, M.J.A.)