1287256-06-7Relevant academic research and scientific papers
Coordination of a hemilabile N,N,S donor ligand in the redox system [CuL2]+/2+, L = 2-pyridyl-N-(2′-alkylthiophenyl) methyleneimine
Schnoedt, Johannes,Manzur, Jorge,Garcia, Ana-Maria,Hartenbach, Ingo,Su, Cheng-Yong,Fiedler, Jan,Kaim, Wolfgang
, p. 1436 - 1441 (2011)
The new copper(I) complexes [Cu(L1)2](BF 4), L1 = 2-pyridyl-N-(2′-methylthiophenyl) methyleneimine, and [Cu(L2)2]-(ClO4), L 2 = 2-pyridyl-N-(2′-benzylthiophenyl)methyleneimine, have been prepared and structurally characterized. In contrast to the known [Cu(L 1)2](ClO4)2, which exhibits partial thioether S binding to effect five-coordinate Cu2+, the copper(I) compounds reported here contain four-coordinate metal ions with exclusively N-donor binding. Cyclic voltammetry reveals a fully reversible oxidation of the CuI species, which suggests a small barrier for reorganization. The reduction at negative potentials is irreversible for compounds [Cu(L) 2](X) and for the structurally characterized new compound [Cu(L 1)(PPh3)2](ClO4). UV/Vis spectroelectrochemistry shows the typical low-energy absorption bands of copper(I) (MLCT transition) and copper(II) (ligand-field transition) in the visible region; the CuII form develops an intense band at 350 nm attributed to a S-to-Cu ligand-to-metal charge transfer (LMCT).
