Sulfonamide vs. sulfonimide: tautomerism and electronic structure analysis of N-heterocyclic arenesulfonamidesElectronic supplementary information (ESI) available: 1H NMR, 13C NMR, IR and UV spectra of compounds 1-10, Cartesian coordinates and absolute energies of all the optimized geometries (PDF). NBO charges for compounds 5A, 5B and 5C, complete crystallographic data of 5 (CIF). CCDC 1504792. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c7nj01353a

• Main Authors: Chourasiya, Sumit S, Patel, Dhara R, Nagaraja, C. M, Chakraborti, Asit K, Bharatam, Prasad V
• Format: Article
• Language: English
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/c7nj01353a

A systematic study of the structure and electronic properties of N-heterocyclic arenesulfonamides (NHAS) was performed using experimental and theoretical methods. Ten new examples of NHAS with pyridine and thiazole N-heterocycles were synthesized. X-ray diffraction studies on one of the compounds suggested that the sulfonimide form is preferred; the molecule exists as a dimer due to two strong intermolecular hydrogen bonds. The possibility of sulfonamide ( N -sulfonylamine) sulfonimide ( N -sulfonylimine) tautomerism was explored using density functional theory (DFT) methods. The energy difference between the two tautomers was small (