Periselectivity, Chemoselectivity, and Regioselectivity of the Cycloaddition Reaction of Aza-Oxyallyl Cations With Cinnamaldehyde: A Density Functional Theory Study

This study theoretically investigates the factors controlling the periselectivity, chemoselectivity, and regioselectivity of the [3 + 2] cycloaddition reaction of aza-oxyallyl cation with cinnamaldehyde to form oxazolidinone. The research utilizes hybrid density functional theory (DFT) method at the B3LYP-D3, B3LYP, M06, and M062X coupled with the 6-311G (d, p) level of theories to explain that the [3 + 2] chemoselective addition of aza-oxyallyl cation across the carbonyl bond of cinnamaldehyde through its C and N reactive sites is more favorable than any other plausible mechanism. Generally, electron-donating groups (EDGs) on aza-oxyallyl cation decrease the activation barriers, whereas electron-withdrawing groups (EWGs) increase the activation barrier. The GEDT values predict a very low polar reaction for the [3 + 2] cycloaddition reaction.