Synthesis of Macrocycles via Orthogonal Bond Cleavage of the Pores in Covalent Organic Frameworks

Control of selectivity in organic synthesis is essential for guiding chemical reactions towards a desired product when multiple outcomes are possible. Since organic reactions can often yield a range of products, selectivity control ensures that the target product is favoured over others. Herein, we present a new synthetic approach, Clip-off Chemistry, which provides precise selectivity control in the synthesis of organic (macro)molecules through selective orthogonal cleavage within extended structures containing such (macro)molecules, which, in turn, spontaneously form when these extended structures are assembled. We have applied this concept to the synthesis of seven novel macrocycles by selectively cleaving double or triple bonds via ozonolysis within covalent-organic frameworks (COFs). With this demonstration, we believe that Clip-off Chemistry will soon provide generalized access to previously inaccessible (macro)molecules and polymers for diverse applications.