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-η²-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(η¹-thiophene) (5). In the absence of a suitable ligand, complex 3 reacts under a nitrogen atmosphere to form Tp(CO)₂Re(μ-N₂)Re(CO)₂Tp (9). An X-ray diffraction study of a single crystal of 9 provides geometric details.