A shuttling molecular machine with reversible brake function

作者：Hirose Keiji^*; Shiba Yoshinobu; Ishibashi Kazuaki; Doi Yasuko; Tobe Yoshito

来源：Chemistry - A European Journal, 2008, 14(11): 3427-3433.

DOI：10.1002/chem.200702001

• crown compounds
• molecular devices
• noncovalent interactions
• photochromism
• rotaxanes

Design, synthesis, and demonstration of a prototype of a shuttling molecular machine with a reversible brake function are reported. It is a photochemically and thermally reactive rotaxane composed of a dianthryl-ethane-based macrocycle as the ring component and a dumbbell shaped molecular unit with two, secondary ammonium stations separated by a phenylene spacer as the axle component. The rate of shuttling motion was shown to be reduced to less than 1 % (from 340 to < 2.5 s(-1)) by reducing the size of the ring component from 30-crown-8 to 24-crown-8 macrocycles upon photoirradiation. The ring component was turned back to 30-crown-8 by thermal ring opening, thus establishing a reversible brake function that works in response to photochemical and thermal stimuli.

• 出版日期2008