Intensified synthesis and post-synthetic modification of covalent organic frameworks using a continuous flow of microdroplets technique

Confining organic building blocks inside a moving system of microdroplets enables high-speed production of catalytic crystals. Covalent organic frameworks are promising for applications such as carbon capture, but it is challenging to rapidly synthesize high-quality, tailored structures. Dong-Pyo Kim from POSTECH, South Korea, and co-workers report that microfluidic devices can produce covalent organic frameworks at a rate of 40 milligrams per hour. This approach injects an aqueous reagent and a carrier oil separately into a capillary and they meet at a T-junction, creating tiny droplets that pass through mixing and heating stages. Energy released by microdroplet flow facilitated β-ketoenamine generation by locking its organic framework in place. The microfluidic setup easily handled post-synthetic modification; the team added palladium to the framework and modified its functional groups to create a catalyst for synthetic coupling reactions.