Direct Synthesis of Dialkylphosphites from White Phosphorus

Abstract

AbstractDialkyl phosphites (DAPIs), traditionally prepared from hazardous and corrosive PCl3, are the fundamental reactive starting materials used in organophosphorus chemistry. Here, a KBr‐mediated synthesis of DAPIs involving P4, alcohols and water is presented. With the use of silica gel as the catalyst, oxone as the safe oxidant, industrially important (EtO)2P(O)H, (i‐PrO)2P(O)H and (MeO)2P(O)H are prepared in 70–90% yields. Furthermore, rare metal extractant bis(2‐ethylhexyl) phosphate (D2EHPA) is obtained in 73% yield. The reaction is characterized by a complete conversion of white phosphorus. Moreover, this method can be easily adapted to large‐scale preparation.magnified image