Dynamic Imine Exchange Reactions for Facile Synthesis of Imine-Linked Covalent Organic Frameworks

Covalent organic frameworks (COFs) are an emerging class of crystalline porous materials with promising applications. However, the lack of an efficient, systematic, and scalable synthesis protocol to produce high-quality COFs with desirable structures still hinders their further promotion and application. Here, based on the concept of dynamic covalent chemistry, we propose to achieve the rapid preparation of imine-linked COFs by employing imine exchange reactions, which allows us to adopt a facile solution stirring refluxing synthetic method due to the change of the reaction type. Such a synthesis protocol not only avoids harsh reaction conditions but also enables us to obtain crystalline COF-300 in 20 min with an ultrahigh space-time yield of >850 kg m –3 day –1 . The resulting product exhibited superior porosity and carbon capture performance compared to that of the previously reported synthetic methods. Moreover, this synthetic strategy can also be extended to the preparation of various imine-linked COFs.