Computational Study of Mechanism of Esterification under Different Catalytic Conditions

Abstract

The reaction mechanism of homogeneous and heterogeneous catalyzed esterification reaction was examined by means of Density functional theory (DFT). The mechanistic investigation showed that the reaction was a two-step process which involved the formation of cyclic transition structures. The theoretical results provide crucial guide to understand the mechanism of acidcatalysed esterification reactions in presence of both homogeneous and heterogeneous catalysts. The structures of catalysts were modeled and their activation energies were determined. A comparison of the activation energies between the homogeneous and heterogeneous catalyzed reactions were done at M06-2X/ 6-31+G* level of theory. The energy diagrams demonstrate the activation energy required decreases in presence of both homo- and heterogeneous catalyzed reactions as compared to the uncatalyzed pathway. The activation energy barrier for the homogeneous catalyzed reaction has the lowest value among all the pathways studied.