An Electric Trap: Electron‐Rich Carbonyl Axis Ends Slow Threading/Dethreading Exchange Dynamics of Pillar[5]arene Ring along Axis. Issue 11 (6th July 2018)

• Record Type: Journal Article
• Authors: Ogoshi, Tomoki; Yamafuji, Daiki; Aoki, Takamichi; Yamagishi, Tada‐aki
• Is Part Of: Israel journal of chemistry. Volume 58:Issue 11(2018)
• Page Start: 1246
• Page End: 1250
• Publication Date: 2018-07-06
• Subjects: pillar[5]arene -- electric trap -- host-guest complexation -- viologen -- carbonyl group; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/ijch.201800019
• Languages: English
• ISSNs: 0021-2148

Abstract

Abstract: Viologen axes with negative carbonyl ends such as carboxylic acid and carbonylethyl groups were synthesized. The threading/dethreading exchange dynamics of the pillar[5]arene ring and these axes were studied by variable‐temperature 1 H NMR and two‐dimensional exchange spectroscopy NMR spectroscopies. The exchange rate increased on introduction of electron‐rich carbonyl ends into the axis: the exchange rate constants of the pillar[5]arene ring along the carboxylic acid‐ended and carbonylethyl‐ended viologen axes were ca. 2000 and 360 times smaller, respectively, than that along the alkyl‐ended viologen axis. Abstract :