Reactivity of Diaminogermylenes with Ruthenium Carbonyl: Ru3Ge3 and RuGe2 Derivatives

Heavier tetrylene- and tetrylyne-transition metal chemistry: it's no carbon copy

Since the late 19th century, heavier tetrylene- and tetrylyne-transition metal chemistry has formed an important cornerstone in both main-group and organometallic chemistry alike. Driven by the success of carbene systems, significant efforts have gone towards the thorough understanding of the heavier group 14 derivatives, with examples now known from across the d-block. This now leads towards applications in cooperative bond activation, and moves ultimately towards well-defined catalytic systems. This review aims to summarise this vast field, from initial discoveries of tetrylene and tetrylyne complexes, to the most recent developments in reactivity and catalysis, as a platform to the future of this exciting, blossoming field.

A diamidinatogermylene as a Z-type ligand in a nickel(0) complex

The reaction of the phosphine functionalized chlorogermylene 1 with Ni(COD)2 (COD = 1,5-cyclooctadiene) afforded the bis-chlorogermylene ligated nickel(0) complex 2 in high yield. The dechlorination reaction of 2 with elemental potassium serendipitously yielded the diamidinatogermylene nickel(0) complex 3. Single-crystal X-ray diffraction analysis reveals that the germanium center in 3 features a pyramidalized geometry, suggesting the germylene moiety in 3 acts as a Z-type ligand, which is further supported by theoretical calculations. Complex 3 represents the first example bearing a Z-type diaminogermylene ligand.

Insertion of germanium atoms in high-nuclearity rhodium carbonyl compounds: synthesis, characterization and preliminary biological activity of the heterometallic [Rh13Ge(CO)25]3−, [Rh14Ge2(CO)30]2− and [Rh12Ge(CO)27]4− clusters

The reaction of [Rh₇(CO)₁₆]³⁻ with Ge²⁺ salts led to the first Rh carbonyl clusters with interstitial Ge atoms.

A triangular triplatinum(0) complex with bridging germylene ligands: insertion of alkynes into the Pt–Ge bond rather than the Pt–Pt bond

A triangular triplatinum(0) complex with bridging germylene ligands was prepared and fully characterized. The Pt₃Ge₃ core is bonded with electron-releasing GePh₂ and PMe₃ ligands. Insertion of alkyne into the Pt–Ge bonds results in the formation of germaplatinacyclic compounds.

Steric effects in the reactions of amidinate germylenes with ruthenium carbonyl: isolation of a coordinatively unsaturated diruthenium(0) derivative

Coordinatively unsaturated germylene-bridged diruthenium(0) complexes have been prepared by treating [Ru₃(CO)₁₂] with amidinate germylenes of the type Ge(R¹bzamR²)(HMDS), but only when the amidinate contains just one very bulky R group (^tBu) (not two).

Expanding the coordination chemistry of donor-stabilized group-14 metalenes

The transformation of an amidinate germylene, equipped with just one accessible lone pair of electrons on the Ge atom, into a bidentate 4-electron donor κ(2)Ge,N-ligand, has been achieved for the first time, opening new doors to the non-carbene-like coordination chemistry of heavier carbene analogues.