Borane-Mediated Carbon Dioxide Reduction at Ruthenium: Formation of C1 and C2 Compounds

One and two: The C2 compound pinBOCH2OCHO (see scheme; HBpin=pinacolborane) and several C1 compounds have been obtained from the borane‐mediated reduction of CO2 under mild conditions with the catalyst precursor [RuH2(H2)2(PCy3)2]. Mechanistic investigation highlights the role of a series of new carbonyl ruthenium complexes that were characterized by multinuclear NMR spectroscopy, IR spectroscopy, and X‐ray diffraction studies.