Nucleophilic substitution at nitrogen atom. N-Alkoxy-N-(dimethoxyphosphoryl)ureas, synthesis and structure

Abstract

N-Alkoxy-N-chloroureas react with trimethyl phosphite in ether forming N-alkoxy-N-(dimethoxyphosphory)ureas. The obtained N-alkoxy-N-(dimethoxyphosphoryl)ureas are the products of the nucleophilic substitution at nitrogen. This reaction is a completely new way to receive the N-phosphorylureas synthetically. By this research the possibility of the N–P bond formation by N-alkoxy-N-chloroureas interaction with P-nucleophiles has been proved. The structure of N-alkoxy-N-(dimethoxyphosphory)ureas has been confirmed by the 1H, 31P and 13C NMR spectra, mass spectra and the XRD study. The XRD study of N-methoxy-N-(dimethoxyphosphory)urea and N-n-butyloxy-N-(dimethoxyphosphory)urea has demonstrated their distinctive structural features. In these compounds both nitrogen atoms have planar configuration. The carbamoyl group and the N–O bond lie within the plane. Thus, it has been found that N-alkoxy-N-(dimethoxyphosphoryl)ureas have a number of structural features different from those of the anomeric ureas.