DFT based computational study on the molecular conformation, NMR chemical shifts and vibrational transitions for N-(2-methylphenyl) methanesulfonamide and N-(3-methylphenyl) methanesulfonamide

This paper presents a DFT quantum chemical investigation of the molecular conformation, NMR chemical shifts and vibrational transitions of N-(2-methylphenyl)methanesulfonamide and N-(3-methylphenyl)methanesulfonamide (C8H11NO2S) employing B3LYP exchange correlation. The vibrational wavenumbers were calculated and the complete assignments were performed on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanics (SQM) method. The 1H and 13C NMR chemical shifts of the compounds were calculated in CDCl3 and DMSO using the GIAO method. Finally, calculations were compared with experimental values.