Absolute Configuration, Predominant Conformations, and Vibrational Circular Dichroism Spectra of Enantiomers of n-Butyl tert-Butyl Sulfoxide

• Published in: Journal of organic chemistry Vol. 66; no. 4; pp. 1122 - 1129
• Main Authors: Drabowicz, Józef, Dudziński, Bogdan, Mikołajczyk, Marian, Wang, Feng, Dehlavi, Afshan, Goring, Joann, Park, Minni, Rizzo, Carmelo J, Polavarapu, Prasad L, Biscarini, Paolo, Wieczorek, Michał W, Majzner, Wiesław R
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 23.02.2001
• ISSN: 0022-3263; 1520-6904
• DOI: 10.1021/jo0011179

Alkylation of the α-carbanion of (R)-(−)-tert-butyl methyl sulfoxide (4) with n-propyl bromide afforded (+)-n-butyl tert-butyl sulfoxide (1) to which the absolute configuration (R) was ascribed. This assignment was confirmed by X-ray analysis of the complex 6 obtained from the enantiomerically pure sulfoxide (−)-1 and mercury chloride. Vibrational absorption and circular dichroism spectra of (+)-1 were measured in CDCl3 solution in the 2000−900 cm-1 region and compared with the ab initio predictions of absorption and VCD spectra obtained with density functional theory using the B3LYP/6-31G* basis set for different conformers of (R)-1. This comparison indicated also that (+)-1 is of the (R)-configuration.