Synthesis, structure and electrochemistry of cationic diruthenium complexes of the type [(N-N)2Ru2(CO)2(?-CO)2(?-OOCFc)]+ containing a ferrocenecarboxylato bridge and two chelating aromatic diimine ligands

The dinuclear bis(ferrocenecarboxylato) complex Ru2(CO)4(?-OOCFc)2(py)2 (Fc = ferrocenyl, py = pyridine) was found to react with arom. diimines (2,2'-dipyridyl, 4,4'-dimethyl-2,2'-dipyridyl, 1,10-phenanthroline, 5-nitro-1,10-phenanthroline, and 5-amino-1,10-phenanthroline) in methanol to give the cationic diruthenium complexes [(N-N)2Ru2(CO)2(?-CO)2(?-OOCFc)]+ (1: N-N = 2,2'-dipyridyl, 2: N-N = 4,4'-dimethyl-2,2'-dipyridyl, 3: N-N = 1,10-phenanthroline, 4: N-N = 5-nitro-1,10-phenanthroline, 5: N-N = 5-amino-1,10-phenanthroline), which have been isolated as the hexafluorophosphate salts. The mol. structure of 3, solved by single-crystal x-ray anal. of the tetraphenylborate salt [3][BPh4], shows a diruthenium backbone bridged by two carbonyl and by one ferrocenecarboxylato ligand, the two 1,10-phenanthroline ligands being in the axial positions. Cyclic voltammetry in dichloromethane reveals for all compds. two successive oxidns. due to ferrocene/ferrocenium redox couple and oxidn. of the diruthenium core. [on SciFinder(R)]