Visible-light-mediated difluoromethylphosphonation of alkenes for the synthesis of CF2P-containing heterocycles

Abstract

Difluoromethylphosphonate, as an in vivo stable phosphate bio-isostere, is an important organofluorophosphine block. In this paper, an efficient and general protocol for the construction of CF₂P-containing heterocycles via visible-light-mediated nucleophilic cyclization of unsaturated carboxylic acids, alcohol and sulfonamides has been developed. This reaction can be carried out smoothly under mild conditions with less catalyst loading, producing several types of CF₂P-containing heterocycles, including CF₂P-lactone, CF₂P-phthalide, CF₂P-tetrahydrofuran and CF₂P-pyrrolidine.