title: Cu(OAc)2-Et3N mediated oxidative coupling of α-azido ketones with pyridinium ylides: utilizing in situ generated imines for regioselective synthesis of imidazo[1,2-a]pyridines.
abstract: Phenacyl azides were reacted with pyridinium ylides in the presence of Cu(OAc)2 (2 mol%) and Et3N utilizing molecular oxygen as a green oxidant to yield imidazo[1,2-a]pyridines in exclusive regioselectivity. Following the optimized protocol, 28 different fused heterocycles were synthesized in high yields (71-92%). In order to get mechanistic insight into the reaction, a few control experiments were carried out and the role of the copper salt was discussed.
authors.affiliation: Department of Medicinal Chemistry and Pharmacology, CSIR-Indian Institute of Chemical Technology, Hyderabad-500007, India. ramaurya@iict.res.in ahmedkamal@iict.res.in.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Kamal
authors.forename: Chada Narsimha
authors.initials: CN
authors.lastname: Reddy
authors.forename: Malasala
authors.initials: M
authors.lastname: Satyaveni
authors.forename: D
authors.initials: D
authors.lastname: Chandrasekhar
authors.forename: Jagadeesh Babu
authors.initials: JB
authors.lastname: Nanubolu
authors.forename: Kiran Kumar
authors.initials: KK
authors.lastname: Singarapu
authors.forename: Ram Awatar
authors.initials: RA
authors.lastname: Maurya
mesh_terms: D001386:Azides / Q000737:chemistry*; D005021:Ethylamines / Q000737:chemistry*; D007097:Imines / Q000138:chemical synthesis* / Q000737:chemistry; D007659:Ketones / Q000737:chemistry*; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry; D011725:Pyridines / Q000138:chemical synthesis* / Q000737:chemistry; D011726:Pyridinium Compounds / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D001386:Azides; D005021:Ethylamines; D007097:Imines; D007659:Ketones; D009942:Organometallic Compounds; D011725:Pyridines; D011726:Pyridinium Compounds; C015092:cupric acetate; C001439:imidazo(1,2-a)pyridine; D010100:Oxygen; C016162:triethylamine