Conversion of thiols into sulfonyl halogenides under aerobic and metal-free conditions12. Issue 9 (27th April 2017)

• Record Type: Journal Article
• Authors: Jereb, Marjan; Hribernik, Luka
• Is Part Of: Green chemistry. Volume 19:Issue 9(2017)
• Page Start: 2286
• Page End: 2295
• Publication Date: 2017-04-27
• Subjects: Environmental chemistry -- Industrial applications -- Periodicals; Environmental management -- Periodicals; 660
• DOI: 10.1039/c7gc00556c
• Languages: English
• ISSNs: 1463-9262

Abstract

Abstract : Highly efficient, aerobic and metal-free conversion of thiols into sulfonyl halogenides was developed. Abstract : An environmentally benign, metal-free synthesis of sulfonyl chlorides and bromides from thiols in the presence of ammonium nitrate, an aqueous solution of HCl and HBr and oxygen as a terminal oxidant was developed. The reactivity of various substituted thiophenols, benzylic-, aliphatic- and heteroaromatic thiols was examined. Ammonium nitrate served as a source of nitrogen oxides (NO/NO2 ), which are the crucial players in a redox-catalytic cycle. Sulfonyl chlorides and bromides were isolated without extraction and "filtered" over a short pad of silica gel; the use of solvents was greatly reduced in comparison with traditional isolation and purification. A "one-pot" protocol for the conversion of thiol into sulfonamide is also demonstrated. Scale-up experiments on the preparation of sulfonyl chloride and bromide are shown. A possible reaction pathway is discussed.