Helicate complexes assembling/disassembling

ASSEMBLING/DISASSEMBLING OF HELICATE COMPLEXES DRIVEN BY THE Cu /Cu" COUPLE... 

The occurrence of the redox-driven reversible assembling-disassembling process involving copper complexes of 16 has been verified through cyclic voltammetry experiments at a platinum electrode in a MeCN solution. Figure 2.17 shows the CV profile obtained with a solution of the double-strand helicate complex [ Cu 21 (16)212 +. 

Figure 2.18 A square scheme illustrating the disassembling of the [Cu2(16)2]2 + double helicate complex, following Cu -to-Cu" oxidation, and the consequent assembling of two [Cun(16)]2+ mononuclear complexes, following the Cu"-to-Cu reduction. The process ultimately derives from the geometrical coordinative preferences of the two oxidation states Cu1 prefers a tetrahedral coordination, which can be achieved with the double helicate arrangement Cu11 prefers a square coordination geometry, which is fulfilled by the coordination of a single molecule of 16.

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