Pyridinium CH⋯anion and π-stacking interactions in modular tripodal anion binding hosts: ATP binding and solid-state chiral induction

Abstract

The preparation of two new tripodal ‘pinwheel’ type anion hosts based on a triethylbenzene core and bipyridinium or ethylnicotinium arms is reported. The new materials bind anions via CH⋯anion interactions. Complexes with Br⁻ and PF₆⁻ have been characterised by X-ray crystallography as both solvates in a pure form. In the bipyridinium host CH⋯F interactions to PF₆⁻ induce a chiral C₃ symmetric conformation that is disrupted in the hydrate. The compound is also selective for ATP²⁻ in aqueous acetonitrile.