The coordination of the B-H bond to a transition metal is fundamentally intriguing due to its connection with the transition metal-mediated B-H bond activation mechanism and catalysis. Most of the...

A series of ruthenium bis(σ‐B−H) borate complexes 1–4 have been prepared by a salt‐elimination protocol using lithium monoaryl trihydroborates Li[ArBH3] (R=Ph, 3,5‐(CF3)2C6H3, o‐tol or Mes) and the corresponding metal halide Cp*Ru(PCy3)Cl. All of these bis(σ‐B−H) borate complexes are stable at room temperature and isolated in good yields (70–92 %). Additionally, treatment of 4 with the hydride abstracting agent B(C6F5)3 generated rare cationic bis(σ‐B−H) borane complex 5. Crystallographic characterization data are provided for 3 and 5. All these new complexes were fully characterized by multinuclear NMR spectroscopy and elemental analysis.