Efficient production of polyrotaxanes from α-cyclodextrin and poly(ethylene glycol)

An alternative synthetic route for polyrotaxanes from commercial dihydroxy- polyethylene glycol (PEG) is developed. This also includes the synthesis of PEG-carboxylic acid (PEG-COOH). The terminal carboxyl groups of PEG were capped with adamantanamine vis-BOP-mediated amination. The novel improvements result in high yield production of polyrotaxanes synthesis with a minimum of reagents, an easy, one-step, high-yield preparation of PEG-COOH of any molecular weight and high degree of modification. The results were compared with those polyrotaxanes that were prepared by previously reported manner, that is, binding of PEG diamino-terminated to adamantaneacetic acid with BOP.