Specific Features of Monomeric Octahedral Monooxo d2-Rhenium(V) Complexes with Oxygen Atoms of Tridentate Chelating (О, N, N) Ligands (Review)

Abstract

Specific features of the structures of 35 mononuclear octahedral monooxo d²-Re(V) complexes with tridentate chelating (О, N, N) ligands [ReO(\({\text{L}}_{{{\text{tri}}}}^{m}\))(\({\text{L}}_{{{\text{bi}}}}^{n}\))], [ReO(\({\text{L}}_{{{\text{tri}}}}^{m}\))(Hal)₂], and [ReO(\({\text{L}}_{{{\text{tri}}}}^{m}\))Cl(PPh₃)] have been considered. It has been demonstrated that, in most of compounds, the Re–O(\({\text{L}}_{{{\text{tri}}}}^{m}\))_trans bonds are comparable in length (or somewhat shorter than) with the Re–O(\({\text{L}}_{{{\text{tri}}}}^{m}\))_cis or Re–O(ST) bonds. This is evidence that the structure contains pseudodioxo ReO₂ groups with an increased multiplicity of both Re–O bonds trans to each other. In the structures of eight compounds, the Re–O(L_tri)_trans bonds are noticeably longer than Re–O(ST) and Re–O(L_tri)_cis owing to the structural manifestation of the trans influence of a multiply bonded oxo ligand.