title: Steric considerations on improving the diastereomeric ratio of (+)- and (-)-neomenthyl phenyl sulfoxides using bulky-headed oxidant hexadecyltrimethylammonium periodate and assignment of their configuration.
abstract: The bulky-headed oxidant hexadecyltrimethylammonium periodate affords the diastereomeric pairs, (Ss)-(+)/(Rs)-(+) and (Ss)-(-)/(Rs)-(-)-neomenthyl phenyl sulfoxides in stereochemically pure states with improved diastereomeric excess (48% diastereomeric excess [de]) as compared to its nonbulky counterpart, sodium metaperiodate (28% de) from respective (+)/(-)-neomenthyl phenyl sulfides. Steric effects involving the head group volume of hexadecyltrimethylammonium periodate is found to play a role in improving the diastereomeric ratio of the products. The two diastereomers can be readily separated by column chromatography. Absolute configuration at the sulfur center in (+)-neomenthyl phenyl sulfoxide was determined by single-crystal X-ray crystallography and found to be Ss. Relative configurations of other sulfoxides were assigned based on the configuration of (+)-neomenthyl phenyl sulfoxide.
authors.affiliation: Applied Chemistry Department, Faculty of Technology & Engineering, The M. S. University of Baroda, Vadodara, Gujarat, India.
authors.forename: Umesh V
authors.initials: UV
authors.lastname: Chaudhari
authors.affiliation: Applied Chemistry Department, Faculty of Technology & Engineering, The M. S. University of Baroda, Vadodara, Gujarat, India.
authors.forename: Deepak
authors.initials: D
authors.lastname: Singh
authors.affiliation: Applied Chemistry Department, Faculty of Technology & Engineering, The M. S. University of Baroda, Vadodara, Gujarat, India.
authors.forename: Pradeep T
authors.initials: PT
authors.lastname: Deota
authors.affiliation: Department of Chemistry, Faculty of Science, The M. S. University of Baroda, Vadodara, Gujarat, India.
authors.forename: Ashutosh V
authors.initials: AV
authors.lastname: Bedekar
keywords: diastereoselective; hexadecyltrimethylammonium periodate; neomenthyl phenyl sulfoxides; steric hindrance