Construction of [1]rotaxanes with pillar[5]arene as the wheel and terpyridine as the stopper

Publication date: Available online 13 April 2019Source: Chinese Chemical LettersAuthor(s): Ling-Ling Zhao, Ying Han, Chao-Guo YanAbstractThe condensation reaction of ω-aminoalkyleneamide-functionalized pillar[5]arenes with 2-(4-([2,2':6',2''-terpyridin]-4'-yl)phenoxy)acetic acid or 4-(4-([2,2':6',2''-terpyridin]-4'-yl)phenoxy)butanoic acid in dry chloroform at room temperature under the catalysis of HOBT/EDCl resulted in novel pillar[5]arene diamido-bridged terpyridine derivatives. 1H NMR and 2D NOESY spectra clearly indicated that the interesting [1]rotaxanes were formed by longer alkylene such as propylene, butylene and hexylenediamido chains threading into the cavity of the pillar[5]arene and with larger terpyridine acting as the stopper. However, the shorter ethylenediamido chain only exists outer of cavity of pillar[5]arene and the molecule exist on free form.Graphical abstract1H NMR and 2D NOESY spectra clearly indicated that the interesting [1]rotaxanes were formed by longer alkylene such as propylene, butylene and hexylenediamido chains threading into the cavity of the pillar[5]arene and with larger terpyridine acting as the stopper. However, the shorter ethylenediamido chain only exists outer of cavity of pillar[5]arene and the molecule exist on free form.
Source: Chinese Chemical Letters - Category: Chemistry Source Type: research