Wolfgang Herrmann, Susanne Wehrle and Gerhard Wenz
Upon UV irradiation in the presence of β-cyclodextrin, (E)-4,4′-bis(dimethylammoniomethyl)stilbene is transformed to the (Z)-isomer, but in the presence of γ-cyclodextrin only the [2 + 2]-cycloaddition products are obtained; the products are a molecular imprint of the cavity of the cyclodextrin.