Dimethylphosphite electrosynthesis from inorganic phosphorus building blocks via oxidative coupling

Abstract

Organophosphorus compounds carry importance in the chemical, medical, and fertilizer industries. Their production often entails the use of white phosphorus or PCl₃, which are toxic and energetically costly to produce. In this work we investigate phosphite ester formation through an electrochemical route which has the potential to serve as a greener alternative. In particular, dimethyl phosphite was electrosynthesized through oxidative coupling of an inorganic P source, H₃PO₂, and methanol as a model building block with high faradaic efficiencies approaching 100%. The reaction is proposed to proceed through electrooxidative phosphorus radical formation followed by coupling of this reactive species with proximal methanol molecules.