β-CD/CuI catalyzed regioselective synthesis of iodo substituted 1,2,3-triazoles, imidazo[1,2-a]-pyridines and benzoimidazo[2,1-b]thiazoles in water and their functionalization

• Published in: Tetrahedron Vol. 73; no. 30; pp. 4295 - 4306
• Main Authors: Dheer, Divya, Rawal, Ravindra K., Singh, Virender, Sangwan, P.L., Das, Parthasarathi, Shankar, Ravi
• Format: Journal Article
• Language: English
• Published: OXFORD Elsevier Ltd 27.07.2017; Elsevier
• Subjects: Chemistry; Chemistry, Organic; Iodo-benzoimidazo[2,1-b]thiazoles; Iodo-imidazo[1,2-a]pyridines; Iodo-triazoles; Physical Sciences; Science & Technology; β-Cyclodextrin; β-Cyclodextrin; Iodo-imidazo[1,2-a]pyridines; Iodo-benzoimidazo[2,1-b]thiazoles; Iodo-triazoles; CYCLIC ADP-RIBOSE; ANALOGS; CLICK CHEMISTRY; CYCLODEXTRIN; lodo-benzoimidazo[2,1-b]thiazoles; EFFICIENT SYNTHESIS; ORGANIC AZIDES; beta-Cyclodextrin; ALKYNE; lodo-imidazo[1,2-a]pyridines; lodo-triazoles; H AMINATION SYNTHESIS; DERIVATIVES; CYCLIZATION
• ISSN: 0040-4020; 1464-5416
• DOI: 10.1016/j.tet.2017.05.081

An environment benign process has been developed for the regioselective synthesis of 5-iodo-1,4-disubstituted-1,2,3-triazoles catalyzed by CuI/β-CD in water. Moreover, the process was manifested for the efficient synthesis of 2-iodo-imidazo[1,2-a]pyridines and 2-iodo-benzoimidazo[2,1-b]thiazoles in aqueous medium. Additionally, the iodinated derivatives were successfully modified via palladium catalyzed coupling reactions. The salient features of this methodology are in-situ formation of 1-iodoalkyne & alkyl/aryl azide under mild reaction conditions, high regio-selectivity and use of water as a greener solvent. [Display omitted]