Synthetic molecular machine based on reversible end-to-interior and end-to-end loop formation triggered by electrochemical stimuli.
We have designed and synthesized a novel [2]pseudorotaxane-based molecular machine in which the interconversion between end-to-interior and end-to-end loop structures is reversibly controlled by electrochemical stimuli. Cucurbit[8]uril (CB[8]) and the thread molecule 3(4+) with an electron-rich hydroxynaphthalene unit and two electron-deficient viologen units form the 1:1 complex 4(4+) with an end-to-interior loop structure, which is reversibly converted into an end-to-end structure upon reduction. Large changes in shape and size of the molecule accompany the reversible redox process. The key feature of the machine-like behavior is the reversible interconversion between an intramolecular charge-transfer complex and viologen cation radical dimer inside CB[8] triggered by electrochemical stimuli.
Lee
Jae Wook
JW
National Creative Research Initiative Center for Smart Supramolecules and Department of Chemistry, Pohang University of Science and Technology, San 31 Hyojadong, Pohang 790-784, Korea.
Hwang
Ilha
I
Jeon
Woo Sung
WS
Ko
Young Ho
YH
Sakamoto
Shigeru
S
Yamaguchi
Kentaro
K
Kim
Kimoon
K
D004563:Electrochemistry; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D008958:Models, Molecular; D015394:Molecular Structure; D013053:Spectrophotometry