Disparate orientation of [1]rotaxanes

A novel [1]rotaxane 2 has been synthesized employing a 4-methyl-benzenesulfonyl and an azobenzene modified β-cyclodextrin (β-CyD) at the 2 position, through self-inclusion complexation and Suzuki-coupling capping in aqueous solution. Disparate absorption, induced circular dichroism (ICD) properties from its isomer [1]rotaxane 1, prepared from the isomeric β-CyD modifier at the 6 position, and the photoisomerization of [1]rotaxane 2 were thoroughly investigated.