Synthesis and properties of a germanium(II) metalloheterocycle derived from 1,8-di(isopropylamino)naphthalene. A novel ligand leading to formation of Ni[Ge[((i)PrN)(2)C(10)H(6)]]4).

A novel mononuclear germylene, Ge[1,8-((i)PrN)(2)C(10)H(6)] (1), was isolated as a stable crystalline solid by the reaction of Li(2)[1,8-((i)PrN)(2)C(10)H(6)] with GeCl(2)(1,4-dioxane). Structural examination of 1 shows that this compound possesses a planar six-membered heterocyclic ring system with a Ge(II) center and that the steric impact of the substituents on the nitrogen centers is greater than that for the related five-membered metalloheterocycles. Compound 1 is readily oxidized with elemental S and Se and the structural details for the dinuclear product [[1,8-((i)PrN)(2)C(10)H(6)]Ge(micro-S)](2) are reported. Furthermore, the lone pair of electrons on the Ge(II) center in 1 allows this species to function as a novel ligand for the preparation of the unique tetrakis(germylene) complex Ni[Ge[((i)PrN)(2)C(10)H(6)]](4) (4). The structural features of 4 are reported and show that the germylene ligand, when coordinated to the Ni(0) center, now exhibited a twisted (nonplanar) heterometallocycle and a cone angle of 145 degrees.