title: Trifluoromethyl acting as stopper in [2]rotaxane.
abstract: A modified dumbbell obtained by replacing one of the phenyl groups of the dibenzylammonium with a strong electron-withdrawing trifluoromethyl group templated the synthesis of the smallest [2]rotaxane reported so far. The trifluoromethyl group not only enhances the templating effect of the dumbbell but also acts as the stopper to prevent dethreading of a [20]crown ether macrocycle.
authors.affiliation: Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543.
authors.forename: Suvankar
authors.initials: S
authors.lastname: Dasgupta
authors.forename: Kuo-Wei
authors.initials: KW
authors.lastname: Huang
authors.forename: Jishan
authors.initials: J
authors.lastname: Wu