ReI(CO)3+ complexes with N∩O− bidentate ligands

Abstract

Simple reactions between Re(CO)₅Cl and 2-benzoxazol-2-ylphenol, 2-benzothiazol-2-ylphenol or 2-(1-methyl-1H- benzoimidazol-2-yl)phenol (performed in boiling toluene) lead to dimeric complexes of general formula Re₂(CO)₆(N∩O⁻)₂. The obtained dimeric species are quite stable in non-coordinating solvents, but in coordinating media (e.g., pyridine – pyr) they undergo disscociative solvolysis to form monomeric derivatives of general formula Re(CO)₃(N∩O⁻)pyr. Molecular structures of both the dimeric and monomeric forms have been confirmed by means of X-ray measurements, electron impact mass spectrometry and IR spectroscopic investigations. UV-VIS absorption and emission properties of the newly synthesized Re(CO)₃⁺ complexes have been investigated and briefly compared with those previously reported for their 8-oxyquinolinato analogues.