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

Abstract

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 wave-numbers 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 H-1 and C-13 NMR chemical shifts of the compounds were calculated in CDCl3 and DMSO using the GIAO method. Finally, calculations were compared with experimental values. (C) 2010 Elsevier B.V. All rights reserved.