One-step synthesis of oxamidato bridged fac-Ru(CO)3 core based dinuclear compounds: Spectroscopic and structural characterisation

Abstract

Oxamidato bridged fac-Ru(CO)3 core based dinuclear compounds of general formula [I(CO)3Ru(μ-L)Ru(CO)3I] (1–3) were synthesised by oxidative addition of oxamide ligands (H2L = N,N′-dibutyloxamide, N,N′-diphenyloxamide, and N,N′-dibenzyloxamide) and iodine to ruthenium carbonyl (Ru3(CO)12) in one-pot reaction under solvothermal conditions. The dinuclear compounds 1–3 were characterised using elemental analyses, IR, UV–Vis and NMR spectroscopic techniques. All these compounds were structurally characterised by single crystal X-ray diffraction methods. The molecular structure of 1–3 consists of a dinuclear framework in which two Ru(CO)3I units are associated together by a bridging oxamide ligand via NO∩ON bis-chelation. The iodide ligands on two ruthenium centres are oriented in a trans-fashion with respect to each other. The reaction proceeded via formation of an iodido bridged intermediate compound [I(CO)3Ru(μ-I)2Ru(CO)3I]. The present account of research comprises a first set of neutral fac-Ru(CO)3 core based dinuclear compounds containing bis-chelating oxamide ligands obtained in single-step.