Terpyridine reversible complex formation

FIGURE 5.1.7 (a) Reversible complex formation of Ru-terpyridine during the BZ reaction, (b) Chemical structure of the terpyridine terminated octa-PEG. (c) Oscillating profile of viscosity of the aqueous solution containing Ru(tpy)rtetra or Ru(tpy)2-octa PEG, HNO3, NaBrOs, and MA at 25°C... 

We achieved autonomous viscosity oscillation by reversible complex formation of terpyridine-terminated PEG and/or terpyridine-terminated tetra PEG in the BZ reaction [26]. Then the BZ reaction induces the periodical binding/dissociation of the Ru-terpyridine complex and causes periodic molecular changes and results in viscosity changes (Fig. 11.7). Differently from the viscosity oscillation we reported before, this mechanism based on complex formation may be advantageous in terms of... 

Ueno, T. Bundo, K. Akagi, Y Sakai, T. Yoshida, R. Autonomous viscosity oscillation by reversible complex formation of terpyridine-terminated poly(ethylene glycol) in the BZ reaction. Soft Matter 2fil0, 6, 6072-6074. 

It has been mentioned previously that the formation of 2 1 Co 02 -peroxodimers is generally believed responsible for the irreversible coordination of dioxygen. In apparent contrast with this affirmation, the mixed bipyridine/terpyridine ligands complex [ Co(terpy)(bipy) 2 (fi-02)]4 +, the molecular structure of which is shown in Figure 16, constitutes an example of reversible coordination of the peroxo group.22... 

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