Triazoles, bridging ligands

Cudzlo S, Nita M. Synthesis and explosive properties of copper(II) chlorate(VII) coordination polymer with 4-amino-1,2,4-triazole bridging ligand. J Hazard Mater 2010 177(l-3) 146-9. 

The dinuclear complex [(bpy)2Ru(bpt)Ir(ppy)2]2+ was reported by Haas-noot et al., Fig. 22b [ 124], In this complex the two metal centers are linked via a bpt bridging ligand containing a mono anionic triazole unit. Because of this electronic feature, the MLCT states localized on the two moieties involve the peripheral ligands and not the bridging ligand. In [(bpy)2Ru(bpt)Ir(ppy)2]2+, emission is only observed from the Ru-based unit and the direction of intercomponent energy transfer is Ir - Ru, i.e., in the opposite direction from that observed for [(bpy)2Ru(HAT)Ir(ppy)2]3+. 

A triazole ligand, (28), leads to asymmetric coordination modes, giving inequivalent metal centers in homobimetallic complexes.94 Complexes of Ru,Os exhibit efficient energy transfer mediated by the triazole ring. Benzimidazole-based bridging ligands like 2,2 -bibenzimidazolate... 

Figure 384 The molecular structures of mononuclear zinc porphyrin dyes (a), Ru-Ru (b), and Ru-Os (c) binuclear complexes containing the bridging ligand 3,5-bis-(pyridin-2-yl)-1,2,4-triazole.

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