Structure of 4,4-bisphenylsulfonyl-N,N-dimethylbutylamine: Interplay of intramolecular C-H·N, C-H·O=S, and interactions

Abstract

Conformations of 4,4-bisphenylsulfonyl-N,N-dimethylbutylamine (BSDBA) were examined by ab initio calculations. Intramolecular CHN, CHO, and interactions are found to play an important role in governing the conformational properties. This finding is supported by charge density analysis based on the theory of atoms in molecules. The calculated molecular structure and 1H chemical shifts of the methyl derivative (BSTBA) are in excellent agreement with experimental findings. The intramolecular CHN hydrogen bond in BSDBA is estimated to have a significant interaction energy of 25 kJ mol-1. The sulfonyl oxygens in BSDBA interact readily with neighbouring methylene, methyl and phenyl hydrogens via CHO=S hydrogen bonds. In agreement with experiment, solvent effect calculations indicate that these weaker intramolecular interactions prevail in an aprotic polar medium. © CSIRO 2009.