Abstract

SYNTHESIS, CHARACTERIZATION, MOLECULAR STRUCTURE, AND HOMO-LUMO STUDY OF 2-PHENYLQUINOXALINE: A DFT EXPLORATION

Ravindra H. Waghchaure* and Thansing B. Pawar

Abstract

Quinoxalines are a versatile class of nitrogen containing heterocyclic compounds and they constitute useful intermediates in organic synthesis. In this paper, we report the synthesis of 2-phenylquinoxaline (2PQXL) from orthophenelyene diamine and phenacyl bromide. The synthesized 2-phenylquinoxaline is characterized by 1HNMR spectral technique. Computational investigation is studied by using density functional theory (DFT) at B3LYP/6-311G(d,p) basis set. The geometry of the 2PQXL molecule is optimized by using B3LYP/6- 311G(d,p) basis set and the geometrical parameters like bond lengths and bond angles have been computed and discussed. Various quantum chemical parameters are determined on the basis of frontier molecular orbital study for the better understanding of chemical behaviour of the title molecule. Molecular electrostatic potential (MEP) is plotted to locate the reactivity sites of the title molecule. A TD-DFT method at B3LYP/6-311G(d,p) has been employed to determine absorption energies along with oscillator strength. In addition, some thermodynamic parameters are also been computed at the same level of theory.

Keywords: 2-Phenylquinoxaline, B3LYP/6-311G(d,p), TD-DFT, Molecular electrostatic potential.