Separation of chiral sulfoxides with chloro substituted chiral selectors in High performance liquid chromatography and synthesis of 2-(4-methylbenzylsulfinyl) benzmide

Author: mari-luiza Konjaria
Co-authors: Natia Shashviashvili
Keywords: Sulfoxides, chiral selector, separation factor.
Annotation:

Asymmetric sulfoxides is a particular case of chirality that may be found in natural as well as synthetic products. About thirty original molecules containing a sulfur atom as a centre of chirality were analyzed in high performance liquid chromatography on chloro substituted polysaccharide-based chiral stationary phases (CSPs) with polar organic compounds- methanol. ethanol, isopropanol and n-Hexane. While all tested CSPs provided enantioseparation for a large part of racemates, cellulose tris (3,5-dichlorphenylcarbamate) proved to be both highly retentive and highly enantioselective towards these species. Abrupt changes in the tendency curves of retention and selectivity were observed when n-hexane proportion reaches about 60% in isopropanol and over 60% it decreases, suggesting that a change in conformation of the analytes and chiral selector is occurring at this point. By systematic variation of the chemistry and structure of chiral selectors and selectands those structural features must be prevailed which are most critical for selector-selectand binding and chiral recognition ability. Synthesis of this some sulfoxides were performed in our laboratory, where was synthesized 2-(4-methylbenzylsulfinyl)benzamide which was suggested to have one of the highest enantioselectivity.