Susceptibility of Sesbagrandiflorain B against Chlorination: A DFT Study

Abstract

Abstract Sesbagrandiflorain B is a novel aryl benzofuran derivative isolated from Sesbania grandiflora. Due to its novelty, there is almost no study on the reactivity and properties on this compound. In this study, we perform calculation to determine the reactivity of sesbagrandiflorain B against chlorination reaction based on fukui indices and energy calculation of reactant, intermediate, and product structures. The properties of the system are calculated using DFT B3LYP/6-311++g(d), and to simulate the effect of solvent we employ polarizable continuum model (PCM) on GAMESS-US 2018 package software. From the structure of sesbagrandiflorain B, there are five possible positions that susceptible to chlorination. The energy of reaction in those positions are significantly different from each other with energy of the intermediate formations are 446.48 kJ, 428.06 kJ, 428.63 kJ, 364.08 kJ, and 388.86 kJ, indicating that the selectivity of sesbagrandiflorain B against chlorination reaction. The intermediate formation of sesbagrandiflorain B chlorination that is simulated without solvent tend to be endothermic while the implementation of PCM to the system significantly reduce the intermediate energy, suggesting that the solvent promote the reaction to be thermodynamically driven. For some position, the solvent also stabilizes the product of chlorination reaction.