DINUCLEAR COMPLEXES CONTAINING FERROCENYL AND OXOMOLYBDENUM(V) GROUPSLINKED BY CONJUGATED BRIDGES - A NEW CLASS OF ELECTROCHROMIC NEAR-INFRARED DYE

Dinuclear complexes with ferrocenyl and oxomolybdenum(V) fragments lin ked by a conjugated spacer have been prepared and studied by spectroel ectrochemistry; the first oxidation (ferrocene --> ferrocenium) afford s spectra characteristic of localized ferrocenium and oxo-Mo(V) fragme nts, but the second oxidation [Mo(V)-->Mo(VI)](VIII results in very in tense new transitions in the near-IR region which we ascribe to a full y allowed pi --> pi transition of the bridging group, which now has q uinonoidal character.