Electronic Structure of Ferrocene-Substituted Cavitands: A QTAIM and NBO Study

Abstract

Ferrocene-substituted tetrakis(methyl)resorcin [4]arenes have been investigated by means of DFT calculations employing the gradient-corrected PBEPBE functional. In comparison with ferrocene and simple ansa-ferrocenes containing 2-4 bridging methylene groups, it was found that the tilt angle of the functionalized cyclopentadienyl (Cp) rings strongly influences the electron density distribution of the ferrocenyl moieties. According to NBO analyses, the iron atoms in the cavitands are more positive in comparison to those in ferrocene, whereas they are less positive in ansa-ferrocenes. The partial charges of carbon atoms belonging to Cp rings show some correlation with the tilt angle.