title: Silver-mediated palladium-catalyzed direct C-H arylation of 3-bromoisothiazole-4-carbonitrile.
abstract: Silver(I) fluoride-mediated Pd-catalyzed C-H direct arylation/heteroarylation of 3-bromoisothiazole-4-carbonitrile (1a) gives twenty-four 5-aryl/heteroaryl-3-bromoisothiazole-4-carbonitriles. The reaction was partially optimized with respect to catalyst, ligand, and base. During this study 3,3'-dibromo-5,5'-biisothiazole-4,4'-dicarbonitrile (3a) was isolated as a byproduct and subsequently prepared via the silver-mediated Pd-catalyzed oxidative dimerization of 3-bromoisothiazole-4-carbonitrile in 67% yield. The analogous phenylation and oxidative dimerization of 3-chloroisothiazole-4-carbonitrile (1b) gave 3-chloro-5-phenylisothiazole-4-carbonitrile (4) and 3,3'-dichloro-5,5'-biisothiazole-4,4'-dicarbonitrile (3b) in 96% and 69% yields, respectively.
authors.affiliation: Department of Chemistry, University of Cyprus, P.O. Box 20537, 1678 Nicosia, Cyprus.
authors.forename: Heraklidia A
authors.initials: HA
authors.lastname: Ioannidou
authors.forename: Panayiotis A
authors.initials: PA
authors.lastname: Koutentis
mesh_terms: D002384:Catalysis; D005459:Fluorides / Q000737:chemistry*; D015394:Molecular Structure; D009570:Nitriles / Q000138:chemical synthesis* / Q000737:chemistry*; D010165:Palladium / Q000737:chemistry*; D018030:Silver Compounds / Q000737:chemistry*; D013844:Thiazoles / Q000138:chemical synthesis* / Q000737:chemistry*
chemical_list: C558509:3-bromoisothiazole-4-carbonitrile; D009570:Nitriles; D018030:Silver Compounds; D013844:Thiazoles; C105022:silver fluoride; D010165:Palladium; D005459:Fluorides