Efficient one-pot synthesis, characterization and  DFT study of solvents polarity effects on the structural, energetic and thermodynamic proprieties of (a-methylamino-ethyl)-phosphonic acid dimethyl ester

Abstract

In this work, an efficient procedure has been described for synthesis of (α-Methylamino-ethyl)-phosphonic acid dimethyl ester (MPDE) via Kabachnik-Fields reaction under green condition, using free solvent and free catalyst by employing microwave irradiation. The designed product is obtained with excellent yield (∼92%) in short reaction time (5–8 min), and confirmed by spectroscopy analyses. Results confirm the successful synthesis of MPDE with high purity. Through appropriate quantum chemical approaches, by the density functional theory (DFT) method, at B3LYP/6–31G* level of theory, we have performed a systematic investigation of the polarity solvent effects on the energetic, structural and thermodynamic proprieties of MPDE in gas phase and in a series of seven solvents of different polarity (water, DMSO, acetonitrile, methanol, ethanol, acetone, and diethylether). The polarizable continuum model (PCM) has been used to obtain the properties in the solvent environment. Results revealed that the participation of the solvent is fundamental for a series of effects concerning the stability and reactivity of the title compound.