Electronic absorption spectra and photodecomposition of some substituted ferrocenes

Abstract

The photostabilities of various ferrocene derivatives in solution have been studied as a function of solvent and, to a lesser extent, of incident wavelength. Some substituted ferrocenes, like ferrocene itself, did not decompose in methanol solution on exposure to near-ultraviolet light or sunlight; the remainder decomposed rapidly. Solutions of some derivatives in a number of other solvents also proved susceptible to photolysis. Qualitative evidence suggests that solute-solvent interaction leads to photochemically unstable species. Ferric ions do not appear to be formed in significant quantities during the degradative processes.Of the substituted ferrocenes investigated in this work, p-acetophenylferrocene appears to have considerable merit as a relatively stable and therefore protective light absorber. None of the derivatives, however, is as stable as ferrocene, which is prohibitively volatile for most practical applications.

Immobilization of Pyrroloquinoline Quinone-Dependent Alcohol Dehydrogenase with a Polyion Complex and Redox Polymer for a Bioanode

“…The 260~280 nm bands of PGA-AmFc were attributed to the adsorption of peptide bonds in PGA. It is known that the UV-visible spectrum of ferrocene changes when the functional groups conjugate with ferrocene rings [30,31]. This is reasonable, since the 440 nm and 326 nm bands of ferrocene were attributed to metal-ring charge transfer, and it appears that the shifted transitions (412 nm and 344 nm bands) in AmFc were of the same type.…”

Photosensitized initiation of vinyl polymerization by a system of ferrocene and carbon tetrachloride

“…However, only a few data have been available for the photosensitized polymerization of vinyl compounds by ferrocene (2). Ferrocene is usually believed to be a light-stable compound, but in organic halide solvents it decomposes upon exposure to light, resulting in the formation of free radicals (3,4). This led us to try the photopolymerization of vinyl monomers using a system of ferrocene and carbon tetrachloride (CCl,) as a sensitizer.…”

Electrochemil investigation of the photodecomposition of selected ferrocene derivatives

“…Several authors report the photodecomposition of a variety of ferrocenes in a range of solvents including decalin [21], iso-octane [21], acetonitrile [21], methanol [21, 221, DMSO [21, 231, pyridine [21, 231, DMF [21, 231, chloroform [20] and carbon tetrachloride [20]. The relationship between decomposition rate and solvent appears to be complex [21] but it is thought that the presence of water in these solvents, even in trace amounts, is the contributing factor to the decomposition process. These photodecomposition studies have all concentrated on the spectroscopic aspects of the photodegradation process but, to the best of our knowledge, no follow up work has been done to determine the affect on the electrochemical properties and hence their direct implications for electrochemical biosensor design and development.…”

“…Although ferrocene is known to be relatively inert in most solvents, with the notable exception of chlorocarbons [20], certain derivatives however have been found to decompose rapidly when exposed to light. Several authors report the photodecomposition of a variety of ferrocenes in a range of solvents including decalin [21], iso-octane [21], acetonitrile [21], methanol [21,221,DMSO [21,231,pyridine [21,231,DMF [21,231,chloroform [20] and carbon tetrachloride [20]. The relationship between decomposition rate and solvent appears to be complex [21] but it is thought that the presence of water in these solvents, even in trace amounts, is the contributing factor to the decomposition process.…”