Formation and dissociation kinetics of dinuclear metal complexes with pyrazole and triazole bridged bis-macrocycles

The kinetics of dissociation and formation of the dinuclear Cu2+ and Ni2+ complexes with L^1 and L^2 have been measured by stopped-flow technique. Whereas the rates of dissociation of the two metal ions from the dinuclear species are very similar, the two steps of the formation of the dinuclear complexes differ by about a factor of 100, indicating that the coordination of the first metal ion strongly influences the binding of the second one.