Reactions of TpRe(CO)₂(THF) with Aromatic Molecules (Tp = Hydridotris(pyrazolyl)borate)

The complex TpRe(CO) 2 (THF) ( 3 ) (Tp = hydridotris(pyrazolyl)borate) reacts with a variety of aromatic molecules to form stable binuclear complexes of the form {TpRe(CO) 2 } 2 (μ-η 2 -η 2 ‘ -L), where L = furan ( 6 ), N -methylpyrrole ( 7 ), or naphthalene ( 8 ). With thiophene, the TpRe(CO) 2 fragment yields the sulfur-bound mononuclear complex TpRe(CO) 2 (η 1 -thiophene) ( 5 ). In the absence of a suitable ligand, complex 3 reacts under a nitrogen atmosphere to form Tp(CO) 2 Re(μ-N 2 )Re(CO) 2 Tp ( 9 ). An X-ray diffraction study of a single crystal of 9 provides geometric details.