We demonstrate a novel method that enables the formation of core-confined bottlebrush copolymers (CCBCs) as catalyst supports. Significantly, owing to the site-isolated effect, these CCBC catalysts with the incompatible acidic para-toluenesulfonic acid (PTSA) and basic 4-(dimethylamino)pyridine (DMAP) groups can conduct a simple two-step sequential reaction in one vessel.

A novel acid–base bifunctional amphiphilic organic nanotube (acid–base-nanotube) containing 1-(2-(prop-2-yn-1-yloxy)ethyl)-1H-imidazole (PEI) groups as basic sites on the wall and benzenesulfonic acid (BSA) groups as acidic sites on the corona of nanotubes was successfully synthesized by a combination of molecular-template core–shell bottlebrush copolymers and click reaction. Owing to the hydrophobic cavity microenvironments, a hydrophilic corona, and site-isolation features of organic tubular structures, the resultant acid–base-nanotube showed high catalytic performance for one-pot deacetalization-Knoevenagel cascade reactions in water.