Preparation of β-Cyclodextrin Polyrotaxane: Photodimerization of pseudo-Polyrotaxane with 2-Anthryl and Triphenylmethyl Groups at the Ends of Poly(propylene glycol)

[structure: see text] A polyrotaxane containing beta-cyclodextrins has been prepared by photoreactions of a precursor complex between beta-cyclodextrin with poly(propylene glycol) having a triphenylmethyl group at one end and a 2-anthryl group at the other end.