Design, Synthesis, and Reactivity of Multidentate Ligands with Rhenium(I) and Rhenium(V) Cores

摘要

> Synthetic pathways to a range of potentially N ₃ O‐tetradentate ligands designed to coordinate to rhenium cores, as well as their coordination behaviors towards different rhenium cores (oxidation states +I and +V) are investigated. Two functionalized N ‐{[1‐(4‐R)‐1 H ‐1,2,3‐triazol‐4‐yl]methyl}‐2‐(pyridin‐2‐ylmethoxy)aniline derivatives L ₁ H (R = methyl acetate) and L ₂ H (R = 4‐nitrophenyl) act exclusively as bidentate ligands and lead to the formation of mononuclear tricarbonylrhenium(I) complexes of the general formula [(LH)Re(CO) ₃ Cl] with L = L ₁ or L ₂ . Both complexes are characterized by 1 H NMR and 13 C NMR, FTIR spectroscopy, electrospray ionization mass spectrometry, and in the case of [(L ₂ H)Re(CO) ₃ Cl] , single‐crystal X‐ray diffraction. The rhenium is coordinated by three carbonyl groups, a chlorine atom and two nitrogen atoms of a triazole group, and a nitrogen of the aniline ring of the ligand, respectively. A theoretical study shows complex [(L ₂ H)Re(CO) ₃ Cl] is the most stable structural isomer. In addition, the oxorhenium(V) complex [(L ₃ )ReO] is isola