Molecular binding behaviors and thermodynamics of ferrocenyl dimethylaminium derivatives by anionic pillar[5]arene

A novel anionic water-soluble pillar[5]arene (4C-WP5A) was synthesized via a convenient synthetic strategy of the direct cyclization of a functionalized hydroquinone monomer. The alkyl chain dependent affinities of ferrocenyl aminiums (FCn+, n: carbon number) with 4C-WP5A are driven by hydrophobic interactions and desolvations with assisted C–H⋯π interactions and electrostatic interactions.