Synthesis and Characterization of a Cationic Ruthenium Complex Featuring an Unusual Bis(η²-BH) Monoborane Ligand

The reaction of Cp*Ru(P ( i )Pr 3)Cl with MesBH 2 (Mes = 2,4,6-trimethylphenyl), followed by chloride abstraction with LiB(C 6F 5) 4.2.5OEt 2 (LiBF 20), afforded the crystallographically characterized complex [Cp*Ru(P ( i )Pr 3)(BH 2Mes)] (+)B(C 6F 5) 4 (-); notably, this represents the first reported cationic complex to feature an eta (2)-BH monoborane ligand, as well as a rare example of bis(eta (2)-BH) ligation.