Electrochromism active units

Electron transfer is an appealing process allowing the same transformation as in photochemistry, i.e., cyclization-reopening. In this context, the DTE unit has proven to be useful for the elaboration of photo and/or electrochromic metal-based systems specially devoted to the control of the electronic communication in bimetallic complexes. Organometallic complexes crmsisting of Jt-conjugated system bridging two redox active metal centers have proven to be efficient molecular wires (Fig. 11). 

Polyhydrazides and poly(amide-hydrazide)s with redox-active carbazole and triphenylamine units have been synthesized [49]. The resulting poly( 1,3,4-oxadiazole)s andpoly(amide-l,3,4-oxadiazole)s show high glass transition temperatures of 288-330 °C and a high thermal stability. The polymers show a weak to medium photoluminescence with emission maxima of 474-506 nm. In addition, the materials show an enhanced redox stability and electrochromic performance. 

The enediyne units play an important role in the structure of various organic molecules. There are three possible isomers (Z)-5.992, ( )-5.993, and gem-5.685. 1,2-Diethynylethene (Z-3-hexene-l,5-diyne) (Z)-5.992, on the one hand, represents a promising structural unit for the synthesis of potential anticancer agents in medicine, which this review reflects. On the other hand, ( -3-hexene-l,5-diyne) (E)-5.993 unit is redox-active and is used as a chromophore for developments in materials chemistry [454-457]. Several instances of redox-active chro-mophores that have new structures with an azulene core have applications in the electrochromic materials area (Figure 5.1) [457]. The cross-conjugated enediyne gem-5.685 unit is rarely used but it is possible to use... 

---