Computational studies on cycloaddition reactions between 1,3-diaza-2-azoniaallene cation and olefins

Density functional theory calculations employing BHandHLYP/6-311+G(d,p) method have been employed in order to quantitatively characterize the mechanism of the title [3+2] reaction between the cationic 1,3-dipolar 1,3-diaza-2-azoniaallene cation and olefins. Computational results indicate that the [3+2] cycloaddition reaction could take place in both concerted and stepwise approaches. No transition states could be located for the approaching pathway between the two reactants: 1,3-diaza-2-azoniaallene and 2-methyl-propene, and thus a 3-membered ring intermediate could be formed directly. The obtained results have also been rationalized with QTAIM theory, and solvent effects and substituent effects have also been elaborated upon herein.