Phosphorylation via the Oxidation of Phosphite. II. The Preparation of the Diesters of Phosphorous Acid by the Reaction of Alcohols with Ethyl N-Phenylimino Phosphite and Acids

Abstract

Abstract The diesters of phosphorous acid were prepared in good yields by the reaction of primary or secondary alcohols, such as methanol, ethanol, and s-butanol, or of phenols, such as phenol, p-chlo-rophenol and p-cresol, with ethyl N-phenylimino phosphite and p-toluenesulfonic acid monohy-drate. Similarly, when carboxylic acids, such as acetic acid, benzoic acid, p-chlorobenzoic acid and trichloroacetic acid, were used in place of the acid monohydrate in the above experiment, the diesters of phosphorous acid were also obtained. Ethyl N-n-propylimino or ethyl N-isopropylimino phosphite could be successfully used in place of ethyl N-phenylimino phosphite in the above experiments. Further, various derivatives of methylphosphinic acid, such as ethyl dicyanomethyl-, ethyl cyanocarboethoxymethyl- and ethyl dicarboethoxymethylphosphinate, were obtained by the reaction of ethyl N-phenylimino phosphite, p-toluenesulfonic acid monohydrate and active methylene compounds, such as malononitrile, ethyl cyanoacetate and diethyl malonate.