Electro synthesis of spirocyclic oxindole and computational studies for investigating the relationship between molecular properties and stability

A novel spirocyclic oxindole derivative was synthesized and subjected to density functional theory (DFT) studies at the B3LYP/6–31 + G** level. Structural parameters and molecular properties such as dipole moments, energy level of the highest occupied molecular orbital (EHOMO) and the lowest unoccupied molecular orbital (ELUMO), and energy gaps were computed. Also, values of donor–acceptor interaction energies and atomic charges were investigated. The best condition for the synthesis of spirocyclic oxindole was the application of propanol as solvent, magnesium as anode, 60 °C as the required temperature, and applying 9.7 F mol−1 electricity to the solution. Under the optimized conditions, some new derivatives of spirocyclic oxindole were synthesized in good-to-excellent yields with high purity.