Syntheses of N-phenylaminomethylenediphosphonic and -diphosphinic acids and their derivatives

Abstract

Substituted aminomethylene diphosphorus-containing compounds are of interest as prmising ligands and biologically active substances [1]. Some of compounds of this type can be obtained by suitable methods using dialkylformamide dialkylacetals [2]. Aiming to synthesize new N-aminomethylenediphosphorus compounds we examined a reaction of some of trimethylsilyl phosphites and hypophosphites taken in excess with the corresponding ethoxymethyleneimine I and formamidine IV obtained similarly to the earlier described procedures [3]. Thus, ethoxymethyleneimine I reacts with a mixture of diethyl(trimethylsilyl)phosphate and diethylphosphite and also with a mixture of tris(trimethylsilyl)phosphate and bis(trimethylsilyl)phosphate at 140–160oС to form diphosphonates II and III. In the zinc chloride catalyst is required for the preparation of compound III (cf. [4]). DOI: 10.1134/S1070363209090230