A DFT Mechanistic Study of the Regio-, Chemo-, and Stereo- Selectivities of the (3 + 2) Cycloaddition of Diarylnitrone Derivatives with 1-(4-Nitrophenyl)-5H-Pyrrolin-2-One

Heterocyclic compounds are vital in rational drug design by providing convenient means for the optimization of drugs or candidates. Isoxazolidine (a heterocyclic compound) derived from (3 + 2) cycloaddition reaction is reported to possess anticancer, antiviral, antibacterial, and anti-inflammatory properties. The mechanistic study chemo-, regio-, stereo-selectivities (32CA) diarylnitrones (A1) 1-(4-nitrophenyl)-5H-pyrrolin-2-one (A2) has been conducted using density functional theory (DFT) method at M06/6-311G (d, p ) computational level. 32CA A1 A2 proceeds through a chemo-selective addition across C=C olefinic bond furnish both kinetically thermodynamically favored routes. effect substitution on studied representative set electron-acceptor electron-releasing groups A2. observed remained unchanged irrespective substituents used reactants, but change kinetics thermodynamics was based substituents. In A2, “exo” cycloadduct formation over “endo” cycloadducts all instances.