Tetranuclear complexes {(#MU#_4-TCNX)[Cu(Me_3TACN)]_4}(BF_4)_4 with TCNX = TCNE, TCNQ or TCNB (1,2,4,5-tetracyanobenzene) and Me_3TACN = 1, 4, 7-trimethyl-1,4,7-triazacyclononane

摘要

The title complexes were obtained as bule solids from the reaction of TCNX ligands with four equiv. of [(CH_3CN)Cu(Me3TACN)](BF_4). The poorly soluble (TCNB) or insoluble compounds (TCNE, TCNQ) exhibit nitrile stretching frequencies compatible with only a moderate metal-to-TCNX electron transfer. This observatoin stands in contrast to results obtained for previously reported tetranuclear species from the reaction of TCNX ligands with complex fragments containing d~6-configurated metal centers (Mn~I, Ru~II, Os~II). The TCNB complex was characterized in solution by cyclic voltametry. ~1H NMR, IR and UV-Vis spectroelectrochemistry and by EPR of the one-electron reduced form.