Revolutionary "Clip-Off" Strategy for Macrocycles from Covalent Organic Frameworks

The synthesis of complex organic macrocycles, particularly large and rigid variants, has long been hampered by low yields, poor selectivity, and arduous purification stemming from stepwise approaches. Sánchez-Naya et al. present a transformative "clip-off" strategy in Science, liberating preformed macrocycles from the pores of designed covalent organic frameworks. By strategically incorporating cleavable bonds into specific covalent organic framework linkers and utilizing precise ozonolysis, near-quantitative yields of macrocycles with ring sizes ranging from 114 to 162 atoms have been achieved. This strategy leverages reticular chemistry to control size and functionality, establishing crystalline frameworks as molecular blueprints.