Syntheses of N2-bridged heterobimetallic complexes, their structural and qualitative bonding analyses

Abstract

A series of N2-bridged (μ-η1:η1-N2) heterobimetallic complexes were prepared by the reaction of the dinitrogen complex [Mo(depe)2(N2)2] (depe = 1,2-bis(diethylphosphino)ethane) with the group IV-VI high valent metal halides [Cp2ZrCl2], NbCl5, TaCl5, MoCl5 and WCl4 via chloride substitution. Compounds [MoCl(depe)2(μ-N2)ZrCp2Cl] (1) and [MoCl(depe)2(μ-N2)M'Cl4(THF)] (2–5, M’ = Nb, Ta, Mo or W) were crystallized from the reaction mixtures. In the case of the reaction with WCl4, disproportionation of W(IV) was suspected but not evidenced. Single crystal X-ray diffraction analyses on all compounds allowed a systematic structural study, and the sketching of qualitative molecular orbital diagrams helped discussing the bonding situation and bolster the structural data.