title: Preparation of 1,7- and 3,9-dideazapurines from 2-amino-3-iodo- and 3-amino-4-iodopyridines and activated acetylenes by conjugate addition and copper-catalyzed intramolecular arylation.
abstract: The conjugate addition of N-formyl derivatives of 2-amino-3-iodo- and 3-amino-4-iodopyridines to acetylenes activated by sulfone, ester, or ketone groups, followed by intramolecular arylation, affords variously substituted 1,7- and 3,9-dideazapurines. The method employs DMF-water as the solvent and copper(II) acetate as the catalyst for the cyclization step. Neither added ligands nor the exclusion of oxygen is necessary. The process therefore provides a simple, convenient, and inexpensive route to this biologically interesting class of products.
authors.affiliation: Department of Chemistry, University of Calgary , 2500 University Drive N.W., Calgary, AB, Canada T2N 1N4.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhu
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Back
mesh_terms: D015761:4-Aminopyridine / Q000031:analogs & derivatives* / Q000737:chemistry*; D000480:Alkynes / Q000737:chemistry*; D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D003500:Cyclization; D008024:Ligands; D011687:Purines / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D000480:Alkynes; D008024:Ligands; D011687:Purines; D003300:Copper; D015761:4-Aminopyridine