Cyclodextrin capped

Moriwaki, F. Kaneko, H. Ueno, A. Osa, T. Hamada, F. and Murai, K. (1987) Excimer Formation and Induced-Fit Type of Complexation of P-Cyclodextrin Capped by Two Naphthyl Moieties, Bull Chem. Soc. Jpn. 60, 3619-3623. 

The supramolecular assembly of (3-cyclodextrin-capped AuNPs on ITO previously coated with a monolayer of ferrocene molecules was shown to exhibit interesting redox properties, as presented in Figure 8.5.25 This is a fine example of the functionalization of a nanoparticle with a functionalized recognition element to create a unique supramolecular scaffold with tailor-made properties. Specifically, the electrocatalytic determination of ascorbic acid was demonstrated by this surface assembly with excellent discrimination over dopamine. 

Other cyclodextrin capped hemes have been prepared using 1-substituted 2-me-thylimidazoles included in an a-cyclodextrin which formed a pentacoordinated complex with protoheme. 

A. Cassez, A. Ponchel, F. Hapiot, E. Monflier, Unexpected multifunctional effect of methylated cyclodextrins in a palladium charcoal-catalyzed Suzuki-Miyaura reaction, Org. Lett., 2006, 8, 4823 826 L. Strimbu, J. Liu, A. E. Kaifer, Cyclodextrin-capped palladium nanoparticles as catalysts for the Suzuki reaction, Langmuir, 2003, 19, 483 85. 

Fig. 5 Two examples of porphyrin-based cooperative optical sensors, (a) A ditopic receptor for binary metal salts. (h) A cyclodextrin-capped porphyrin system able to sense and report in four distinguishable association modes. ...

Y. Shi, J. Goodisman, and J.C. Dabrowiak, Cyclodextrin capped gold nanoparticles as a delivery vehicle for a prodrug of cisplatin, Inorg. Chem., 52 (16), 9418-9426, 2013. 

Supramolecular organic/inorganic hybrids have been produced using gold nanoparhcles and [60]fullerene [109]. Kaifer and coworkers prepared y-cyclodextrin-capped gold nanoparhcles (3.2 nm diameter), which combined to form water-soluble network aggregates with a diameter of approximately 300 nm in the presence of [60]fullerene. In the particles, complexation of y-cyclodextrins and [60]... 

A number of capped cyclodextrins which are able to bind a metal ion at one end of their cavity, together with an organic guest in the cavity, have been synthesized. Such species parallel in several respects the family of completely synthetic vaulted transition-metal complexes prepared by Busch and coworkers and already discussed in Chapter 3 (section 3.5). 

The hydrolysis of esters by the nickel derivative (271) provided an early example of the use of a metal-capped cyclodextrin as a catalyst (shown here as its p-nitrophenyl acetate inclusion complex) (Breslow Overman, 1970 Breslow, 1971). The synthesis of this host involves the following steps (i) covalent binding of the pyridine dicarboxylic acid moiety to cyclodextrin, (ii) coordination of Ni(n) to this species, and (iii)... 

Table A5.6 Effect of capping on the cleavage of esters by /3-cyclodextrin. ...

Double Heck reaction, 42 494 Double layer interface, 30 223-225 Double nucleophilic displacement, capped cyclodextrin, 32 437 Double-pulse method, 38 31 Double recognition models, 32 451 52 Doublet mechanisms, 30 43, 45, 47 Drago parameters, 38 212 Drougard-Decrooq equation, 30 345, 356, 371 Dry evaporation, perovskite preparation, 36 246-247... 

Fig. 11.—Schematic Diagram of the Interaction of a Guest with Gamma Cyclodextrin Bearing Two Naphthyl Groups. [Ueno and coworkers proposed two possible mechanisms of inclusion, I and 2. In 1, one of the naphthyl groups acts as a space regulator. In 2, the two naphthyl groups form a flexible, hydrophobic cap across the cavity of the cyclodextrin. In the cases of the guests that they investigated, Ueno considered that mechanism 2 is predominant.]...

A novel diaza crown ether capped j3-cyclodextrin has been prepared (172) as outlined in Scheme 9. It should be noted that the cap is attached to the face of... 

We describe how we prepared and characterized gold nanoparticles ( 3 nm in diameter) capped with thiolated cyclodextrins. The CD-capped nanoparticles are hydrophilic, and they bind compounds derivitized from ferrocene as evidenced by values measured by NMR spectroscopy. (Adapted from Liu et al., 2001)... 

The preparation and characterization of gold nanoparticles ( 3 nm in diameter) capped with thiolated cyclodextrins are described. The CD-capped... 

Scheme 4. Conversion of benzophenone-capped cyclodextrin to dideoxy derivative.

Specific (or selective) polyfunctionalization of cyclodextrin is, in principle, possible based upon stepwise regiospecific flamingo-type capping as is shown schematically in Scheme 5. Simple tetrasubstitution (or hexasubstitu-tion) is more easily attained through double (or triple) capping. A typical example is the successful preparation of tetrasubstituted /J-cyclodextrin (8), prepared from 7 by the authors as a channel-forming compound for metal ion transport (77). 

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