Studies in phosphorylation. Part XXIX. The synthesis of dialkyl phosphates from monoalkyl phosphonates: direct oxidative esterification

Abstract

Dialkyl hydrogen phosphates, RO(R′O)PO₂H, are produced from monoalkyl hydrogen phosphonates, RO(HO)PHO, by oxidation either with bromine in pyridine or with carbon tetrachloride and triethylamine with stoicheiometric quantities of an alcohol. In the absence of an alcohol, the former reagent gives sym-dialkyl dihydrogen pyrophosphates in good yield. The nature of the phosphorylating entity in each system is discussed.

The preparation of a nucleoside diphosphonate is described and the hydrolysis of dialkyl phosphonates (RO)₂PHO, to monoalkyl hydrogen phosphonates has been re-examined.