Theoretical investigation of the chemoselectivity and synchronously pyrazole ring formation mechanism from ethoxymethylenemalononitrile and hydrazine hydrate in the gas and solvent phases: DFT, meta-GGA studies and NBO analysis

Abstract

Chemoselectivity of the nucleophilic attack of nitrogen atom has been changed in the presence of the solvent due to Rds changes.

Theoretical Evaluation of the Efficiency of Novel Frustrated Lewis Pairs in the cis-Hydrogenation Reaction of Dimethylacetylene

“…However, the solvent increases the energy of the overall reaction from -41.61 to -42.18 kcal mol -1 . Based on the work of Simón and Goodman [67] and Sabet-Sarvestani et al [68], using a hybrid meta-GGA functional produces reasonably good results in comparison to the experimental data. Therefore, in order to achieve greater accuracy in the results obtained for FLP1, singlepoint energy calculations on the gas phase optimised structures have been carried out using the meta-GGA functional at the MPWB95/6-311++G (d,p) level.…”

The origin of experimental regioselectivity in ring-closing reaction of pyrido[1,2-e]purine systems and comparison of the aromaticity character of probable products: a mechanistic study based on DFT insights

“…Regarding the previous experiments, [32][33][34][35][36] investigation of kinetic aspects of the two paths and also the justification of the origin of the observed regioselectivity behavior are the main purposes of this investigation. As a main idea, the aromatic characters of the rings of the formed products may have a relationship with the observed kinetic-control regioselectivity.…”