The first cobalt metallacrowns: Preparation and characterization of mixed-valence cobalt(II/III), inverse 12-metallacrown-4 complexes

Stamatatos TC; Dionyssopoulou S; Efthymiou G; Kyritsis P; Raptopoulou CP; Terzis A; Vicente R; Escuer A; Perlepes SP

Inorganic Chemistry, Vol.44, No.10, 3374-3376, 2005

Stamatatos TC, Dionyssopoulou S, Efthymiou G, Kyritsis P, Raptopoulou CP, Terzis A, Vicente R, Escuer A, Perlepes SP

Aerobic reactions of Co(O2CMe)(2)&BULL; 4H(2)O with di-2-pyridyl ketone oxime (Hpko) in the presence of counterions (CIO4-, PF6-) give the tetranuclear, mixed-valence cobalt(II/III) clusters [Co-2(II)-Co-2(III)(OR)(2)(O2CMe)(2)(pko)(4)S-2]X-2 [R = H, S= MeOH, X = CIO4 (1); R = Me, S = EtOH, X = PF6 (2)] depending on the solvent mixture. Complexes 1 and 2 are the first Co members in the family of metallacrowns adopting the extremely rare inverse 12-metalla-crown-4 motif.