[Ir(ppy)(2)(CN)(2)](-) (ppy = anion of 2-phenylpyridine) and some substituted derivatives have been investigated for their ability to interact with additional metal cations, both in solution and the solid state, via the externally-directed cyanide lone pairs, and to act as energy-donors in the resulting assemblies. [Ir(ppy)(2)(CN)(2)](-) is slightly solvatochromic, showing a blue-shift of the lowest energy absorption manifold in water compared to organic solvents, and the solubilised (t)Bu-substituted analogue [Ir((t)Buppy)(2)(CN)(2)](-) [(t)Buppy = anion of 2-(4-(t)Bu-phenyl)pyridine] is also metallochromic with coordination of the cyanide lone pairs to two M(II) cations in MeCN (M = Ba, Zn) resulting in blue-shifts of the lowest-energy absorption and emission maxima. These effects are however modest because of (i) the presence of only two cyanide groups, and (ii) the fact that the lowest-energy excited state has a substantial (3)LC component and is therefore not purely charge-transfer in nature. Crystallisation of [Ir(ppy)(2)(CN)(2)](-) as its (PPN)(+) salt in the presence of excess of lanthanide(III) salts leads to formation of assemblies based on Ir-CN-Ln bonds, which generate in the solid state either Ir(2)Ln(2)(μ-CN)(4) square assemblies or linear trinuclear species with Ir-CN-Ln-NC-Ir cores. In the Ir(2)Eu(2)(μ-CN)(4) and Ir(2)Nd(2)(μ-CN)(4) complexes the Ir-based emission is substantially quenched due to energy-transfer to lower-lying f-f states of these lanthanide ions. In addition reaction of [Ir(F(2)ppy)(2)(CN)(2)](-) [F(2)ppy = cyclometallating anion of 2-(2,4-difluorophenyl)pyridine] with [Re(phen)(CO)(3)(MeCN)][PF(6)] in solution affords dinuclear IrRe and trinuclear IrRe(2) species in which {Re(phen)(CO)(3)} units are attached to the N-donor termini of one or both of the cyanide groups; these complexes have been structurally characterised and display quantitative Ir→Re energy-transfer, showing luminescence only from the Re(I) terminus on excitation of the Ir(III) unit.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.