Cyclometalated Ir(iii) complexes with bulky 2-arylphenanthroimidazole ligands possess tunable optical properties and demonstrate unusually high reactivity.

A series of cyclometalated Ru(II) complexes with 2-arylbenzimidazoles antenna ligands bearing electron-donor/withdrawing substituents and anchoring 4,4′-dimethoxycarbonyl-2,2′-bipyridine have been prepared and their structure, optical and electrochemical properties have been studied. The...

Iridium(III) is often considered to be one of the most inert octahedral metal ions. Herein we present a phenanthroimidazole-based bis-cyclometalated iridium(III) chloride undergoing a facile chloro ligand exchange with iodine, in a gas-solid reaction under ambient conditions. Monitoring the progress of the reaction by X-ray diffraction analysis reveals the crystal-packing-induced exceptional stereoselectivity of this topochemical transformation. The results provide excellent opportunities to modulate the geometry and kinetic properties of cyclometalated iridium(III) complexes that may be very promising in catalysis and design of anticancer agents.

Though 2-arylperimidines have never been used in iridium(III) chemistry, the present study on structural, electronic and optical properties of N-unsubstituted and N-methylated 2-(2-thienyl)perimidines, supported by DFT/TDDFT calculations, has shown that these ligands are promising candidates for construction of light-harvesting iridium(III) complexes. In contrast to N-H perimidine, the N-methylated ligand gave the expected cyclometalated μ-chloro-bridged iridium(III) dimer which was readily converted to a cationic heteroleptic complex with 4,4′-dicarboxy-2,2′-bipyridine. The resulting iridium(III) dye exhibited panchromatic absorption up to 1000 nm and was tested in a dye-sensitized solar cell.

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Conventional cyclometalation of calix[4]arene bis(aryltriazoles) with iridium(III) chloride hydrate leads to unique meso architectures in which the Ir2Cl2 core is cross-bound by two (C^N)2-ligands, that allows further replacement of the...

The title compounds, 2-(pyridin-2-yl)-1H-perimidine (C16H11N3; 1), 1-methyl-2-(pyridin-2-yl)-1H-perimidine (C17H13N3; 2), and 1,3-dimethyl-2-(pyridin-2-yl)-1H-perimidinium iodide (C18H16N3 +·I−; 3) were synthesized under mild conditions and their structures were determined by 1H NMR spectroscopy and single-crystal X-ray analysis. The N-methylation of the nitrogen atom(s) at the perimidine moiety results in a significant increase of the interplane angle between the pyridin-2-yl ring and the perimidine system. The unsubstituted perimidine (1) forms a weak intramolecular N—H...N bond that consolidates the molecular conformation. In the crystal structures of 1–3, the molecular entities all are assembled through π–π and C—H...π interactions.