Excision of organic macrocycles from covalent organic frameworks

Molecules are typically synthesized through stepwise processes involving chemical reactions between simple molecular precursors. Here, we report an advance in the synthesis of new organic molecules based on the approach of clip-off chemistry, in which molecules are excised from ordered, extended organic structures. We synthesized macrocycles by selectively cleaving them out of covalent organic frameworks. The synthesized macrocycles include eight macrocyclic polyamides with 114-, 138-, and 162-atom rings, and one 114-atom ring macrocyclic polyimide. This excision approach expands the scope of chemical organic synthesis to previously inaccessible macromolecules.