Synthesis and Characterization of Carbonyl–Ruthenium Trisubstituted‐Germylene Compounds

Owing to the remarkable physical properties and versatile chemistry of germanium, the synthesis of ruthenium–germylene compounds offers broad application potential and addresses important practical demands. In this study, we explored the substitution reactivity of germylene ligands both prior to and following coordination to transition metals. Using the ferrocenylacetylene‐supported germylene FcC ≡ CGe(NArCMe) 2 CH ( 1 , Fc = (η 5 ‐C 5 H 4 )Fe(η 5 ‐C 5 H 5 )) as a precursor, the bis(germylene)‐coordinated ruthenium complex Ru(CO) 3 [FcC ≡ CGe(NArCMe) 2 CH] 2 ( 2 , Ar = 2,6‐iPr 2 C 6 H 3 ) was synthesized. Treatment of the carbonyl–ruthenium–germylene compound Ru(CO) 3 [ClGe(NArCMe) 2 CH] 2 ( 3 ) with a reducing agent, followed by workup, afforded a novel ruthenium–germylene complex, Ru(CO) 4 [(OH)Ge(NArCMe) 2 CH] ( 4 ). In this species, the chlorine atom bound to germanium is replaced by a hydroxyl group, and only a single germylene ligand coordinates to the ruthenium center. In contrast, the reaction of complex 3 with tricyclohexylphosphine (PCy 3 ) yielded the previously reported compound Ru(PCy 3 ) 2 (CO) 3 ( 5 ). The molecular structures of complexes 2 and 4 were confirmed by X‐ray crystallography and spectroscopic analyses, while the structure of 5 was verified by comparison with literature data.