Mechanosynthesis of polymer α-aminophosphonates

Abstract

Kabachnik–Fields reaction is widely used to obtain α-aminophosphonates, including polymeric ones. In addition, methods for the mechanosynthesis of α-aminophosphonates under mechanosyn-thesis conditions are being developed. The article examined methods for the preparation of aryl-substituted polymeric α-aminophosphonates by reacting isomeric diaminobiphenyls, terephthalic aldehyde and diethylphosphonate in the absence of a solvent in a ball mill. As a result, polymeric α-aminophosphonates 4 were obtained. The structure of the products was established on the basis of 1H, 31P and IR NMR spectra. In the 1H NMR spectrum, it should be noted the presence of charac-teristic signals of the protons of aromatic fragments in the form of multiplets at 8.62, 8.07 and 7.54 ppm, signals of the proton at the sp3-hybridized carbon atom in the form of a broadened singlet at 3.75 ppm, as well as a signal of the protons of the group OСH2CH3 as a multiplet at 4.14 ppm. and a multiplet at 1.20 ppm. In the 31P spectrum there was the presence of a phosphorus signal at 22.96 ppm. Absorption bands at 1161 cm–1 (P=O), 1051 cm–1 (P-C-O), 2957 cm–1 (OCH3) and 3445 cm–1 (NH amide fragment) were observed in the IR spectra. Additionally, the possibility of post-modification of polyvinyl chloride (PVC) with fragments of α-aminophosphonates was investigat-ed by reacting the former with 2-aminothiophenol, benzoaldehyde and diethylphosphonate in the absence of a solvent in a ball mill, as well as by reacting with 2-aminothiophenol, terephthalic aldehyde and diethylphosphonate under similar conditions. Thus, a possibility of mechanosynthesis of α-aminophosphonates was demonstrated, as well as the possibility for the post-modification of PVC with fragments of α-aminophosphonates.