DFT study of the possible mechanisms for the synthesis of α-cyanophosphonates from β- nitrostyrenes

Abstract

Abstract In this article, the theoretical study of the reaction mechanism of the addition of triphenyl phosphite to β-nitrostyrene is discussed. The M062X method, which is a subset of density functional theory (DFT) and def2svp basis set, was used to determine the appropriate mechanism. To accomplish this, the structures of the starting materials, products, intermediates, and transition states were optimized, and their respective energies were obtained. For this purpose, three plausible reaction mechanisms were proposed, denoted as paths a, b, and c. In the pathway a, triphenyl phosphite is added to the β-position of β-nitrostyrene. The b pathway is designed in such that the triphenyl phosphite molecule is added to the oxygen of nitro in β-nitrostyrene, and in the c pathway, triphenyl phosphite is added to the nitrogen of the β-nitrostyrene compound. Since the presence of two ml mol of triphenyl phosphite is required to carry out the reaction and form the desired product, all three routes of the proposed mechanism were designed accordingly. by evaluating potential reaction pathways and comparing their energetics, a plausible mechanism for the reaction can be proposed.