Heterogeneous catalysts for selective oxidation of C-H bonds were synthesized by co-polymerization of new N-heterocyclic carbene-palladium(II) (NHC-Pd ) monomers with divinylbenzene. The polymer-supported NHC-Pd -catalysed undirected C-H acetoxylation of simple and methylated arenes as well as polyarenes, with similar or superior efficiency compared to their homogeneous analogues. In particular, the regioselectivity has been improved in the acetoxylation of biphenyl and naphthalene compared to the best homogeneous catalysts. The new polymer-supported catalysts maintain the original oxidation state of Pd after repeated catalytic reactions, and exhibit no significant leaching of palladium. In addition, the new catalysts have been successfully recovered and reused without loss of activity over several cycles of reactions.

In situ XAS is used to reveal the evolution of palladium species during an undirected C–H acetoxylation reaction.

An N-heterocyclic carbene palladium(II) complex containing two anthracene side arms was immobilized on the surface of reduced graphene oxide (rGO) by π-stacking. The activity of the homogeneous analogue and the supported complex in undirected C-H acetoxylation reaction of arenes was [a]

In the title compound, [Pd(C11H9N)(C13H14N2)Cl2], the PdII ion is coordinated by two Cl anions, one carbene C atom and one pyridine N atom in a slightly distorted square-planar geometry. In the crystal, the mol­ecules are linked through weak C—H⋯Cl hydrogen bonds into a tape structure.

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