Aryl triflates: useful coupling partners for the direct arylation of heteroaryl derivatives via Pd-catalyzed C-H activation-functionalization.
Aryl triflates were found to be suitable partners for the palladium catalyzed direct arylation of heteroaromatics via C-H activation-functionalization. The reaction conditions and the catalyst have a determining influence on the yields. The system combining PPh3 and Pd(OAc)2 using KOAc as base and DMF as solvent promotes the selective 2- or 5-arylations in moderate to high yields. Several heteroaromatics such as furan, thiophene, thiazole or oxazole derivatives have been employed successfully. The electronic properties of the aryl triflates also have a decisive influence on the yields of the coupling products. Electron-rich aryl triflates gave satisfactory results, whereas the electron-poor ones led to the formation of phenols.
Roger
Julien
J
Institut Sciences Chimiques de Rennes, UMR 6226 CNRS-Université de Rennes "Catalyse et Organometalliques", Campus de Beaulieu, 35042 Rennes, France.
Doucet
Henri
H
D002384:Catalysis; D005663:Furans / Q000737:chemistry; D008698:Mesylates / Q000737:chemistry*; D010080:Oxazoles / Q000737:chemistry; D010165:Palladium / Q000737:chemistry*; D013844:Thiazoles / Q000737:chemistry; D013876:Thiophenes / Q000737:chemistry
D005663:Furans; D008698:Mesylates; D010080:Oxazoles; D013844:Thiazoles; D013876:Thiophenes; C045880:methanesulfonic acid; D010165:Palladium; C039281:furan