A functionalized Ge3-compound with a dual character of the central germanium atom.

(cAAC)Ge(GeL)2 (1) (cAAC = cyclic alkyl(amino) carbene; L = PhC-(tBuN)2), a functionalized Ge3-compound was prepared. Quantum mechanical studies on 1 show a reciprocal relationship between the electronic state of the central tri-coordinated Ge atomand its reactivity towards protons, viz. tetravalent Ge(0) in terms of bonding and divalent Ge(0) in terms of reactivity. Thus the central Ge atomcan be considered as having a hidden but highly reactive lone pair of electrons. However, the terminal Ge atoms can be considered as tri-coordinated divalent Ge(I) with an active lone pair of electrons.