Catalyst- and solvent-free click synthesis of cyclodextrin-based polyrotaxanes exploiting a nitrile N-oxide.

A catalyst- and solvent-free synthesis of cyclodextrin-based polyrotaxanes exploiting a stable nitrile N-oxide as an end-capping agent was achieved. The C-C bond-forming end-capping reaction of an allyl-terminated pseudopolyrotaxane with the nitrile N-oxide proceeded smoothly by solid-state grinding in a mortar to afford a polyrotaxane.