The quantum mechanical (QM) density functional theory (DFT) calculations for the model reaction of 6a with methoxide were carried out in Jaguar . After the initial rough MacroModel minimisation, the structures were geometrically optimised at M06-2X/6-31G**++ level and solvent effects were modelled by self-consistent reaction field method using the Poisson-Boltzmann (PBF) solver in water. The structures were checked for the absence of imaginary frequencies to confirm that they correspond to geometric minima. The ultrafine pseudospectral grids were used for the geometry optimisation, followed by full analytic integrals for single point frequency calculation at M06-2X/aug-cc-pVTZ(-f) level with PBF solver in water. For anionic intermediates, the stop_rxn=3 and geoconv_mode=standard keywords had to be used to successfully model the unstable intermediates. The transition state was located using the QST (quadratic synchronous transit) method and further verified by the presence of one imaginary frequency in the direction of the reaction coordinate and by an intrinsic reaction coordinate scan (IRC) in direction of both reactants and products. The calculated total energies for reactants, intermediates, and products were compared to calculate the reaction energetics.