Heterometallic Germanium(IV) Complexes Based on the N-Phenyl-Substituted o-Amidophenolate Ligand.

New bimetallic complexes PhAPGe[M(CO)nCp]2 (PhAP is 3,5-di-tert-butyl-N-(phenyl)-o-ami-nophenolate dianion; M = Fe, n = 2 (II); M = W, n = 3 (III)) are synthesized by the insertion of O,N-heterocyclic germylene PhAPGe (I) at the metal–metal bond in dimers [Fe(CO)2Cp]2 and [W(CO)3Cp]2. The oxidation of compounds II and III with silver(I) triflate affords paramagnetic germanium(IV) o-iminosemiquinolates detected by EPR spectroscopy. The oxidative addition of 3,6-di-tert-butyl-o-benzoquinone to germylene I proceeds via the oxidation of the low-valence center to the tetravalent state and is accompanied by symmetrization with the formation of the corresponding bis-o-amidophenolate and bis(catecholate) derivatives of germanium(IV). Digermylene oxide Ia synthesized by the hydrolysis of starting germylene I acts as the oxidant in the reaction with the nickel cyclopentadienylcarbonyl dimer and forms an eight-membered metallocycle supporting four Ge(II)–Ni(II) donor–acceptor bonds in compound (CpNi)2[PhAP-GeOGePhAmP]2 (PhAmP is 3,5-di-tert-butyl-N-(phenyl)-o-aminophenolate anion) (IV). The molecular structures of compounds II–IV are determined by X-ray diffraction (XRD) (СIF files CCDC nos. 2118153–2118155, respectively). [ABSTRACT FROM AUTHOR]