Transformation of an Imine Cage to a Covalent Organic Framework Film at the Liquid–Liquid Interface

Abstract

Dynamic covalent chemistry (DCC) opens up a fascinating route for the construction of well‐organized supramolecular architectures, starting from organic molecular cages to crystalline macromolecular covalent organic frameworks (COFs). Herein, for the first time, we have manifested a facile room‐temperature DCC‐directed transformation of discrete organic imine cage‐to‐COF film at the liquid–liquid interface. The unfolding of the cage leading to the generation of imine intermediates, followed by their interface‐assisted preorganization and subsequent growth of the COF film, are elucidated through detailed spectroscopic and microscopic investigations. The interfacial cage‐to‐COF transformation provides a facile route for the faster fabrication of free‐standing COF films with high porosity and crystallinity, demonstrating excellent performance towards molecular sieving and high solvent permeance. Thus, the current study opens up a new route for structural interconversion between two crystalline entities with diverse dimensionality employing DCC at the confined interface.