Palladium‐Catalysed Direct C‐H Activation/Arylation of Heteroaromatics: An Environmentally Attractive Access to Bi‐ or Polydentate Ligands

Bi‐ or polydentate ligands based on heterocycles can be easily prepared by palladium‐catalysed C–H bond activation of heteroaromatics followed by heteroarylation with heteroaryl bromides. A variety of heteroaromatics such as furans, thiophenes, pyridines, thiazoles or oxazole derivatives have been employed and moderate to good yields were generally obtained using the air‐stable complex [PdCl(dppb)(C3H5)] as catalyst. A range of functions such as acetyl, formyl, ester or nitrile on the heteroaromatics is tolerated.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)