Inorganic Chemistry, Vol.39, No.1, 141-152, 2000
Binuclear 1,2,4,5-tetraimino-3,6-diketocyclohexane bis[bis(bipyridine)ruthenium(II)] redox series
The reaction of the [Ru(bpy)(2)(MeOH)(2)](2+) cation (bpy = 2,2'-bipyridine) with 1,2,4,5-tetraaminobenzene in the presence of trace water and oxygen yields the cation [(bpy)(2)Ru(1,2,4,5-tetraimino-3,5-diketocyclohexane)Ru(bpy)(2)](4+). This binuclear species undergoes ligand-based reductions, giving the 3+ and 2+ charged species. The X-ray structure, electrochemistry, ZINDO calculations, and NMR, ESR, UV/vis, and IR spectra were analyzed where possible, giving an electronic model of the binuclear species and some of its redox products. The X-ray structure reveals the [(bpy)(2)Ru] fragments symmetrically disposed across the 1,2,4,5-tetraimino-3,5-diketocyclohexane bridge in a molecule with C-s symmetry.
Keywords:TRANSITION-METAL COMPLEXES;DIFFERENTIAL-OVERLAP TECHNIQUE;DINUCLEAR RUTHENIUM COMPLEXES;PARA-BENZOQUINONE DIIMINE;INTERMEDIATE NEGLECT;ELECTRONIC-STRUCTURE;BRIDGING LIGAND;CHARGE-TRANSFER;MOLECULAR SWITCH;BIS(BIPYRIDINE)RUTHENIUM(II)3;4-DIAMINO-3;4'-DIIMINO-3;4'-DIHYDROBIPHENYL