Density functional theory for N–O bond dissociation enthalpies of quinoxaline-1,4-dioxide derivatives: Theoretical method assessment and prediction

The performance of a variety of density functional theories (DFT) used for calculating N–O bond dissociation enthalpies (BDEs) of quinoxaline-1,4-dioxide derivatives is examined. It was observed that mPW1PW91, B3LYP, B1B95, and BMK functionalities significantly outperformed other popular density functional theory methods, including B3PW91, B1LYP, and B3P86. In particular, the mPW1PW91 method was recommended because of its accuracy. Subsequently, first, second, total, and mean N–O BDEs for a new synthetic veterinary medicine, Quinocetone, were determined. The predictions obtained via the mPW1PW91 were 240.4, 251.0, 508.4, and 254.2 kJ mol⁻¹, respectively.