A Metal‐Containing N‐Heterocyclic Germylene Based on an Oxalamidine Framework

A metal‐containing N‐heterocyclic germylene based on a N ‐mesityl (Mes)‐substituted oxalamidine framework is reported. The precursor (MesN=) 2 C–C(–N(H)Mes) 2 ( 1 H 2 ) was converted into its rhodium complex [Rh(κ 2 N‐ 1 H 2 )(cod)][OTf] ( 2 ) (cod = 1,5‐cyclooctadiene; OTf = triflate) in 62 % isolated yield. Subsequent reaction of 2 with Ge{N(SiMe 3 ) 2 } 2 gave the crystalline N‐heterocyclic germylene [Rh(cod)(μ‐ 1 )Ge][OTf] ( 3 ) in 50 % yield. The compounds under study were fully characterized by various methods, also including X‐ray crystallographic studies on single crystals of 2 and 3 . Density functional theory (DFT) calculations revealed that π conjugation in the bridging oxalamidine framework is increased and n(N)–p(Ge) π bonding is decreased upon κ 2 N metal coordination; a further weakening of the Ge–N bond occurs through triflate coordination to the Ge II atom. Nevertheless, preliminary coordination studies revealed that 3 behaves as 2‐electron ( L ‐type) germylene donor ligand. Treatment of 3 with [Ir(cod)Cl] 2 furnished the heterobimetallic complex [Rh(cod)(μ‐ 1 )Ge‐Ir(cod)Cl][OTf] ( 4 ), as evidenced by NMR spectroscopic investigations and DFT calculations.