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Updated: Jan 2, 2026

Synthesis and Characterization of Supramolecular Colloids
Published on: April 22, 2016
Modular supramolecular dimerization of optically tunable extended aryl viologens
Magdalena Olesińska1, Guanglu Wu1, Silvia Gómez-Coca2
1Melville Laboratory for Polymer Synthesis , Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge , CB2 1EW , UK .
Abstract:
Cucurbit[8]uril (CB[8]) mediated assembly of extended aryl viologens (EVs) into optically tunable dimers is reported for the first time. We show that the modular design and synthesis of a new class of π-conjugated viologen derivatives with rigid aromatic or heteroaromatic bridging units as well as electron donating molecular recognition motifs enable their self-assembly into 2 : 2 complexes with CB[8]. The quantitative dimerization process involving these two molecular components in an aqueous solution enables excimer-like interactions between closely packed charged guests giving rise to distinct spectroscopic behavior. The nature of these dimers (CB[8]2·(EV[X]R)2) in the ground and excited states was characterized by NMR, isothermal titration calorimetry, and steady-state spectroscopic measurements.
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