Crystal structure and quantum chemical calculations of (E)1‐benzyl‐3‐((4‐methoxyphenyl)imino)‐5‐methylindolin‐2‐one

• Published in: Journal of heterocyclic chemistry Vol. 58; no. 8; pp. 1601 - 1609
• Main Authors: Abdel El‐wahab, Hend A. A., Hamdy, Ahmed K., Schulzke, Carola, Aboul‐Fadl, Tarek, Qayed, Wesam S.
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Inc 01-08-2021; Wiley Subscription Services, Inc
• Subjects: Crystal structure; Crystallography; Imines; Isomers; Molecular orbitals; NMR spectroscopy; Quantum chemistry; Structural analysis
• ISSN: 0022-152X; 1943-5193
• DOI: 10.1002/jhet.4284

The known Schiff base compound, (E)1‐benzyl‐3‐((4‐methoxyphenyl)imino)‐5‐methylindolin‐2‐one, was prepared as before by reacting 1‐benzyl‐5‐methylindoline‐2,3‐dione with 4‐methoxyaniline. The product was unambiguously characterized using elemental analysis, 1H and 13C‐NMR spectroscopy, and its new single‐crystal X‐ray structural analysis. Molecular orbital calculations were conducted in order to investigate the structures and relative stabilities of the (E) and (Z) isomers of 1‐benzyl‐3‐([4 methoxyphenyl]‐imino)‐5‐methylindolin‐2‐one. Specific attention was paid to the (E) isomer. The available crystallographic experimental data for the latter ensured also validation of the model structures computationally derived at the theoretical B3LYP/6‐31G(d,p) level.
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