Synthesis of a cyclodextrin azo dye [3]rotaxane as a single isomer

Abstract

Azo coupling between 2,6-dimethylphenol and aqueous 4,4′-bis(diazonio)azobenzene chloride in the presence of α-cyclodextrin yields an azo dye [3]rotaxane as a single stereoisomer, with the 2,3-rims of both cyclodextrins pointing outwards.