Closed , half-open , and open ferrocenes: Redox behavior and electron spin resonance of the radical cations

Article abstract of DOI:10.1021/om00130a029

Successive opening of one or both rings of ferrocene results in a cathodic shift of the redox potential for the couple ferrocene/ferricinium, increased chemical lability, and vastly decreased g anisotropy in the ESR spectra of the respective complex radical cations. As opposed to closed ferricinium, ESR of the open ferricinium ions is observed at room temperature. These findings are discussed on the basis of the electronic structure as suggested by INDO MO calculations.