Ferrocene derivatives as receptors to explore ammonium cation–π interactions

Abstract

The potential importance in biology of ammonium–arene cation–π interactions has fostered the development of a model system that uses ferrocene as a scaffold that can rotate groups with respect to each other while maintaining them at a fixed distance. The preparation of 1-benzyl-1′-N,N-dimethylaminomethylferrocene methiodide is reported along with the solid state structure of it and its precursor. Clear evidence is presented for an intermolecular ammonium–arene interaction. The results are analyzed in the context of existing arene–ammonium ion contacts.