Polymeric dirhenium(III) complexes of the type [cis-Re2(O2CCH3)2Cl4(LL)]n involving the symmetrical linker ligands pyrazine, 4,4′-bipyridine, and methylenebis(diphenylphosphine oxide)

The reactions of the dirhenium(III) complex cis-Re2(μ-O2CCH3)2Cl4(H2O)2 with the linker ligands pyrazine (pyz), 4,4′-bipyridine (4,4′-bpy) and methylenebis(diphenylphosphine oxide) (dppmO2) in acetone solution have been used to prepare the polymeric complexes [cis-Re2(μ-O2CCH3)2Cl4(μ-pyz)]n (1), [cis-Re2(μ-O2CCH3)2Cl4(pyz)]2(μ-pyz) (2), [cis-Re2(μ-O2CCH3)2Cl4(μ-4,4′-bpy)]n (3) and [cis-Re2(μ-O2CCH3)2Cl4(μ-dppmO2)]n (4). The structures of all four complexes (1–4) have been determined and show that the ReRe distances are 2.2358(8), 2.240(2), 2.2512(4) and 2.2438(4) Å, respectively. The structure of 2 shows the presence of terminal and bridging pyrazine ligands, while the polymeric complex 3 possesses both planar and twisted bridging 4,4′-bipyridine ligands.