Synthesis of 1,1-dialkylindolium-2-thiolates via base-induced transformation of 4-(2-chloro-5-nitrophenyl)-1,2,3-thiadiazole in the presence of secondary amines.
4-(2-Chloro-5-nitrophenyl)-1,2,3-thiadiazole undergoes ring-opening to produce a thioketene intermediate that reacts with secondary amines forming 2-(2-chloro-5-nitrophenyl)-N,N-dialkylthioacetamides. Intramolecular cyclization of these thioamides via nucleophilic substitution of the halogen on the aromatic ring affords nonaromatic 1,1-dialkylindolium-2-thiolates instead of the expected aromatic N,N-dialkylaminobenzo[b]thiophenes.
Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, USA. daa@dartmouth.edu
Dmitry A
DA
Androsov
D000081:Acetamides; D000588:Amines / Q000737:chemistry*; D003500:Cyclization; D013438:Sulfhydryl Compounds / Q000138:chemical synthesis*; D013830:Thiadiazoles / Q000737:chemistry*
D000081:Acetamides; D000588:Amines; D013438:Sulfhydryl Compounds; D013830:Thiadiazoles