Reactivity of a N‐Coordinated Germylene‐Borane Complex: From Ge→B to Ge→Ga Coordination

Abstract

Reactivity studies of the GeII→B complex L(Cl)Ge⋅BH3 (1; L=2‐Et2NCH2‐4,6‐tBu2‐C6H2) were performed to determine the effect on the GeII→B donation. N‐coordinated compounds L(OtBu)Ge⋅BH3 (2) and [LGe⋅BH3]2 (3) were prepared. The possible tuning of the GeII→B interaction was proved experimentally, yielding compounds 1‐PPh2‐8‐(LGe)‐C10H6 (4) and L(Cl)Ge⋅GaCl3 (5) without a GeII→B interaction. In 5, an unprecedented GeII→Ga coordination was revealed. The experimental results were complemented by a theoretical study focusing on the bonding in 1−5. The different strength of the GeII→E (E=B, Ga) donation was evaluated by using energy decomposition analysis. The basicity of different L(X)Ge groups through proton affinity is also assessed.