Electron Donor–Acceptor Systems in Electrochemiluminescent Chiral Covalent Organic Frameworks for Enantioselective Discrimination

Abstract The fabrication of chiral covalent organic frameworks (CCOFs) with electrochemiluminescence (ECL) properties tailored for enantioselective sensing remains challenging. This study employs a post‐synthetic modification strategy to synthesize ionic CCOFs with pronounced ECL behavior. First, an achiral covalent organic framework is constructed via imine condensation. Subsequently, the imidazolyl group in the COF is covalently functionalized with optically pure, chlorine‐substituted chiral reagents, forming an imidazolium moiety. Within this engineered architecture, the imidazolium and pyrenyl units serve as the electron acceptor and donor components, respectively. The obtained ionic CCOFs exhibit strong ECL activity. When applied as chiral sensors, the achieved ECL‐active CCOFs demonstrate a consistent recognition pattern: ( S )‐CCOFs exhibit deeper ECL quenching toward ( S )‐analytes. The ECL intensity ratios between the ( R )‐ and ( S )‐analytes range from 1.6–13.1. Moreover, a robust correlation is observed between analyte concentration (or enantiomeric composition) and ECL intensity.