Applicable Properties of Cucurbiturils

Abstract

This account highlights three significant fields of applications for cucurbiturils (CBs). The first relates to cucurbituril‐based devices and sensors involving spectral effects associated with the formation and dissociation of inclusion complexes. The second refers to the use of CBs as catalysts that control the rate and selectivity of chemical reactions. The third deals with the potential use of CBs for the assembly of mechanical devices and molecular motors. An example of the sensor application is based on the discovery that 4‐aminobipyridine derivatives form strong inclusion complexes with CB6, exhibiting remarkably large enhancements of fluorescence intensity and quantum yields. This reversible binding phenomenon can be used for the design of switchable beacons that can be incorporated into cascades of binding networks for various applications. The second application is exemplified by selective, enhanced photoaddition reactions as well as [3+2]cycloaddition and other reactions mediated by the CB cavity. The third application is based on the idea that low‐barrier molecular rotary motors having rotaxane architecture can be constructed using a cucurbituril host and a polyyne guest serving as stator and rotator, respectively. The “low friction” between these components is supported by molecular mechanics calculations with model systems and experimentally verified by X‐ray crystallography with several synthetic host–guest complexes, all suggesting that the diyne rod floats at the center of the macrocyclic host with no apparent van der Waals contacts between them.

Cucurbiturils: from synthesis to high-affinity binding and catalysis

“…4,42,64,188,197,198,201 Photochemical applications are facilitated by the fact that CBn are optically transparent in the near UV and the visible region, with the exception of some chromophore-modified derivatives. [225][226][227] In fact, other macrocyclic hosts (e.g., cyclodextrins, [168][169][170][171] calixarenes, 228,229 and the octaacid host 230,231 ) have also been widely used as molecular containers for intermolecular photochemical reactions.…”

Advances in the lanthanide metallosupramolecular chemistry of the cucurbit[n]urils

“…The Q[n]s and their substituted derivatives have now been employed for a range of applications that include their use as artificial ion channels, vesicles, stationary phases in chromatography, electrochemistry (including ISEs), molecular machines as well as for the synthesis of polymers and as components for inclusion in a range of nanomaterials [42,[48][49][50][51][52][53][54][55][56]. Q[n]s are capable of acting as ligands by virtue of their equivalent pair of electron-rich sets of carbonyl oxygen atoms fringing each portal.…”

Effective Stabilization of cis-Isomer of Styryl Dye inside the Cucurbit[7]uril Cavity

“…Наиболее привлекательным среди всех гомологов явля-ется CB [7] благодаря относительно хорошей раствори-мости в воде, возможности взаимодействия с большим набором ароматических молекул, катализу их химиче-ских и фотохимических превращений, а также способно-сти модулировать процессы, протекающие в возбужден-ном состоянии. [9][10][11][12][13][14] В частности, весьма перспективной является идея управления процессом фотохимической изомеризации с помощью комплексообразования фото-активных молекул и СВ [7]. Однако, несмотря на очевид-ный потенциал применения, известно лишь ограничен-ное число примеров, в которых контроль за проведением реакции фотоизомеризации осуществляется посред-ством взаимодействия с CB [7].…”