An iron germylene complex having Fe-H and Ge-H bonds: synthesis, structure and reactivity.

A base-free iron germylene complex Cp*(CO)(H)Fe[double bond, length as m-dash]GeH{C(SiMe)} (1) was synthesised by abstraction of pyridine from a germyl complex Cp*(CO)(py)FeGeH{C(SiMe)} (2), which was prepared by treatment of Cp*Fe(CO)(py)(Me) with HGeC(SiMe). X-ray crystallographic analysis revealed that 1 has an Fe-Ge bond that is the shortest among those ever reported. Reactivity of 1 toward several polar unsaturated organic compounds was investigated. Complex 1 underwent stoichiometric hydrogermylation of carbonyl compounds such as ketones, aldehydes and isocyanates (RNCO) at room temperature. In contrast, the reactions of 1 with isothiocyanates (RNCS) resulted in clean cleavage of the C[double bond, length as m-dash]S double bonds.