New Alkyl Organo Complexes of Ruthenium: X-ray Molecular Structure of a [Hydridotris(pyrazolyl)borato]methylruthenium Complex, [RuTp*(CH3)(cod)] (Tp* = Hydridotris(3,5-dimethylpyrazolyl)borate, cod = 1,5-Cyclooctadiene), Containing an Unusual Three-Center B(μ-H)Ru Bond

The reaction of [RuCl 2 (cod)(bpzm)] ( 1; cod = 1,5-cyclooctadiene, bpzm = bis(pyrazol-1-yl)methane) with MeMgCl gives [RuMeCl(cod)(bpzm)] ( 2 ). This complex reacts with AgCF 3 SO 3, affording [RuMe(CF 3 SO 3 )(cod)(bpzm)] ( 3 ) and AgCl. [RuTpMe(cod)] ( 4 ) and [RuTp*Me(cod)] ( 5 ) were prepared from the reaction of 3 with KTp (Tp = hydridotris(pyrazolyl)borate) and KTp* (Tp* = hydridotris(3,5-dimethylpyrazolyl)borate), respectively. Compound 5 was characterized by X-ray diffraction. The molecule shows unusual coordination of the hydridotris(3,5-dimethylpyrazolyl)borate ligand, where a three-center B(μ-H)Ru bond was found.