Homoleptic trimethylphosphane complexes of transition metals, such as [Mo(PMe 3 ) 6 ] (2-Mo) [1] and [W(PMe 3 ) 6 ] (2-W), [2] form a class of rare and very reactive compounds. [3][4][5] The high reactivity of these complexes originates from the combination of strong s-donor and weak p-acceptor properties of the PMe 3 ligand, which leads to very electron-rich metal centers [6] that are capable of activating s bonds. A consequence of the high reactivity of the metal centers and the steric pressure caused by the PMe 3 ligands in the complexes [M(PMe 3 ) 6 ] (M = Mo, W) is the facile dissociation of one PMe 3 ligand to afford, through an intramolecular C À H bond activation, the cyclometalated products [M(h 2 -CH 2 PMe 2 )H(PMe 3 ) 4 ]. [1,2] The complexes [M(PMe 3 ) 6 ] and their cyclometalation products are subject to various ligand displacement and oxidative addition reactions. [7] We report here a new reaction type of these electron-rich metal complexes that involves a Ge À Cl bond heterolysis of an aryl germanium(II) chloride to form metal-germanium triple bonds.
A new method was developed for the synthesis of the starting materials [Mo(PMe 3 ) 6 ] (2-Mo) and [W(h 2 -CH 2 PMe 2 )H(PMe 3 ) 4 ] (2-W-c) involving the reduction of trans-[MCl 2 (PMe 3 ) 4 ] (1-M; M = Mo, W) [8,9] with sodium [