Preparation, Structure, Bonding, and Preliminary Reactivity of a Six-Coordinate d⁴ Osmium–Boryl Complex

The d⁴ ML₆ bis-boryl complex OsH­(Bcat)₂Cl­(PⁱPr₃)₂ (Bcat = catecholborate) has been prepared by the reaction of OsH₂Cl₂(PⁱPr₃)₂ with HBcat, via the monoboryl intermediate OsH₂(Bcat)­Cl­(PⁱPr₃)₂, and its structure determined by X-ray diffraction analysis. The Os–B bonds and the stability and disposition of the boryl ligands have been analyzed by DFT calculations. The bis-boryl complex loses HBcat to give Os­(Bcat)­Cl­(CO)₂(PⁱPr₃)₂, under a CO atmosphere.