Petronilho, AnaAnaPetronilhoMüller-Bunz, HelgeHelgeMüller-BunzAlbrecht, MartinMartinAlbrecht2015-05-152015-05-152014 Elsev2015-01Journal of Organometallic Chemistryhttp://hdl.handle.net/10197/6563Imidazo[1,2-a]pyridine consisting of a pyridine fused to an imidazolium salt at the imidazolium N1–C2 bond and hence protected from forming normal imidazole-2-ylidene complexes undergoes selective activation of the C5–H bond with Ag2O, i.e. at the imidazolium carbon that is proximal to the pyridine nitrogen. While the silver carbene complex is unstable, transmetallation with [IrCp*Cl2]2, [RuCl2(cym)]2, and [PdCl(allyl)]2 afforded stable mesoionic carbene complexes. Two iridium(III) complexes containing one fused carbene ligand and one palladium(II) complex containing two carbene ligands at the metal centre were structurally characterized. The absence of substituents adjacent to the carbene carbon prevents wingtip group activation, and it imparts a reduced stability of the complexes in particular under (mildly) acidic conditions.enThis is the author’s version of a work that was accepted for publication in Journal of Organometallic Chemistry. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Journal of Organometallic Chemistry (VOL 775, ISSUE 2015, (2015)) DOI: 10.1016/j.jorganchem.2014.03.021 .N-heterocyclic carbeneMesoionicFused abnormal carbeneRuthenium(II)Iridium(III)Palladium(II)Journal Article77511712310.1016/j.jorganchem.2014.03.0212015-05-13https://creativecommons.org/licenses/by-nc-nd/3.0/ie/