The organozinc rich compounds [Cp*M(ZnR)5] (M = Fe, Ru; R = Cp*, Me, Cl, Br).

Organozinc (ZnR with R = Cp*, Me, Cl, Br) ligated transition metal (M) half-sandwich compounds of general formula [CpM(ZnR)5] (M = Fe, Ru) are presented in this work. The new compounds were obtained by treatment of various GaCp ligated precursors with suitable amounts of ZnMe2 to exchange Ga against Zn. This exchange follows a strict Ga:Zn ratio of 1:2. Accordingly, a Ga/Zn mixed compound [{CpRu(GaCp)(ZnCp*)(ZnCl)2}2] can be obtained if the amount of ZnMe2 is reduced so that one GaCp* remains coordinated to the transition metal. All new compounds were characterized by elemental analysis, (1)H and (13)C NMR spectroscopy as well as by single crystal X-ray diffraction techniques, if applicable. The coordination polyhedra of [CpM(ZnR)5] can be derived from the pseudo homoleptic parent compound [Ru(ZnCp)4(ZnMe)6], as emphasized by continuous shape measures analysis (CShM). Computational investigations at the density functional theory (DFT) level of theory were performed, revealing no significant attractive interaction of the zinc atoms and therefore these compounds are best described as classical complexes, rather than cluster compounds. The Ru-L bond strength follow the order Cp* > ZnCl > ZnMe > ZnCp*.