Stereoselective oxidation of sulfides to sulfoxides by n-chloramines

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2014

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İpek, Halil

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Chiral sulfoxides are present in many biologically active compounds. Asymmetric synthesis of the sulfoxides has been performed by chiral metal complexes and chiral peroxides. Although the asymmetric organooxidation of sulfides by chiral peroxides proved to be successful, peroxides are difficult to handle and obtain. In this study, a new metal free method has been developed to oxidize sulfides to chiral sulfoxides with easily accessible chiral N-chloramines. For this purpose, chiral reagents were synthesized and chlorinated to yield N-chloramines. In oxidation reactions, chiral information has been transferred to sulfides with the transfer of chlorine onto sulfur from nitrogen. With N-chloramines, we observed enantioenriched sulfoxide formation. The results were also subjected to computational studies. These studies revealed that the amine-Cl goes through anion pair intermediate while imide-Cl transfers chlorine in an SN2 fashion. The observed results have been promising, yet the conditions still need to be further optimized.

Subject Keywords

Sulfides., Sulfoxides., Oxidation., Chloramines., Asymmetry (Chemistry).

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http://etd.lib.metu.edu.tr/upload/12617964/index.pdf
https://hdl.handle.net/11511/24139

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

H. İpek, “Stereoselective oxidation of sulfides to sulfoxides by n-chloramines,” M.S. - Master of Science, Middle East Technical University, 2014.