Half-sandwich ruthenium, rhodium and iridium complexes containing dipyridyl amine based ligands

Abstract

Compounds derived from the reactions of dimeric arene ruthenium [{(η⁶-arene)Ru(μ-Cl)Cl}₂] (arene = benzene and p-cymene) and structurally analogous rhodium and iridium complexes [{(η⁵-C₅Me₅)M(μ-Cl)Cl}₂] (M = Rh or Ir) with 2-chloro-4,6-(di-2-pyridylamino)-1,3,5-triazine (cddt) and 2,4,6-tris(di-2-pyridylamino)-1,3,5-triazine (tdat) are reported. Compounds under investigation have been characterized by elemental analyses, NMR (¹H and ¹³C), electronic absorption, emission spectral and electrochemical studies. Structures of the dinuclear compounds [{(η⁶-C₁₀H₁₄)RuCl}₂ (cddt)](PF₆)₂, [{(η⁵-C₅Me₅)RhCl}₂ (cddt)]Cl₂•6H₂O and trinuclear compound [{(η⁶-C₆H₆)RuCl}₃ (tdat)]Cl₃•4H₂O have been determined crystallographically. Among cddt containing compounds the {(η⁶-C₁₀H₁₄)RuCl}- units in [{(η⁶-C₁₀H₁₄)RuCl}₂ (cddt)](PF₆)₂ are anti, while {(η⁵-C₅Me₅)RhCl}- in the rhodium compound [{(η⁵-C₅Me₅)RhCl}₂ (cddt)]Cl₂•6H₂O are syn with respect to triazine ring. Cyclic voltammetric studies on the compounds suggested lack of communication between the metal centres. Furthermore, although tdat is luminescent at room temperature compounds under investigation containing this ligand are non-luminescent in acetonitrile.