Iodine-promoted radical alkyl sulfuration of imidazopyridines with dialkyl azo compounds and elemental sulfur. Issue 8 (6th February 2019)

• Record Type: Journal Article
• Authors: Gao, Yong-Chao; Huang, Zhuo-Bin; Xu, Li; Li, Zhao-Dong; Lai, Zhi-Sheng; Tang, Ri-Yuan
• Is Part Of: Organic & biomolecular chemistry. Volume 17:Issue 8(2019)
• Page Start: 2279
• Page End: 2286
• Publication Date: 2019-02-06
• Subjects: Chemistry, Organic -- Periodicals; Bioorganic chemistry -- Periodicals; Chemistry, Physical organic -- Periodicals; 547
• DOI: 10.1039/c8ob03191f
• Languages: English
• ISSNs: 1477-0520

Abstract

Abstract : Dialkyl azo compounds were found to be effective alkyl radical sources for direct alkyl sulfuration with imidazopyridines using elemental sulfur under metal-free conditions. Abstract : Dialkyl azo compounds were found to be effective alkyl radical sources for direct alkyl sulfuration with imidazopyridines using elemental sulfur under metal-free conditions. Iodine, an inexpensive and mild reagent, could promote alkyl sulfuration. A variety of quaternary cyanoalkyl radicals were successfully coupled with elemental sulfur. A subsequent C–H sulfuration of imidazopyridines afforded a diverse array of imidazopyridine derivatives bearing cyanoalkylthio groups. The cyano group could be modified and further underwent condensation with 2-aminothiazole to afford an interesting heterocyclic amide. Control experiments showed that iodine could greatly suppress the self-coupling of cyanoalkyl radicals, thus making the sulfuration proceed smoothly.