Synthesis and characterization of ferrocenylgalvinol, a novel d–π redox system

✍ Scribed by Hideyuki Tukada

• Publisher: Elsevier Science
• Year: 2008
• Tongue: French
• Weight: 328 KB
• Volume: 49
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/j.tetlet.2008.04.019

✦ Synopsis

A novel d-p redox molecule bearing ferrocene (Fc) and galvinoxyl (GalO) units as reversible redox active sites has been synthesized and characterized. The molecule shows solvatochromic behavior and changes from a red color in n-hexane (k max = 388, 541 nm) to a greenish brown (k max = 413, 582 nm) in MeOH. A cyclic voltammogram of 1 under neutral conditions shows a redox process corresponding to Fc/Fc Å+ but not one for GalOH (or GalO À )/GalO Å . Under basic conditions the latter process was observed and it occurred at a lower oxidative potential (E 1 1=2 ¼ À0:074 V vs Ag/AgCl) than the former process ðE 2 1=2 ¼ 0:498 VÞ. Thus 1 shows potential as a bilateral multi-redox molecule with pH dependence. Chemical oxidation of 1 under basic conditions (aq KOH, K 3 Fe(CN) 6 ) gives an EPR spectrum with an hfc of 1.2 G attributable to Fc-GalO Å .