Organic Reactions Mediated by y-CD

A modified y-CD bearing an 0-2-naphthylacetyl substituent prodnced larger overall ester hydrolysis rates in water (pH 8.7) than native y-CD. A 12-fold increase was observed for p-nitrophenyl acetate, arising from both an inaeased rate of intracomplex hydrolysis 

Redox reactions can be controlled by complexes between one host and two guest molecules. For example, the redox reaction between A -benzylnicotinamide and ninhydrin was affected by the addition of CD. y-CD facilitated the formation of the ternary complex of catalyst-substrate-y-CD in a 1 1 1 ratio, in which the redox reaction proceeded. However, j8-CD inhibited the formation of the catalyst-substrate complex, decreasing the reaction rate. This is an example in which the CD cavity controlled the catalyst-substrate complex formation.  

Higher selectivity has been reported using 3,6-anhydro-y-CD instead of native y-CD. It has been known that anhydro-CD has a distorted cavity. Interestingly, the isomer- and 

The different complexation properties of the trans- and cis-AzCD are attributed to the difference in cavity size induced by the configuration of the azo double bond. It is assumed that the cavity of cis-AzCD is deeper than both that of trans-AzCD and native CD. The cavity of trans-AzCD might be shallow and broader. This is the reason why the first guest molecule binds more strongly than the second. p-Nitrophenylacetate was hydrolyzed 

These results hold particular interest in the reversed photoregulated system of molecular functions. Thus, the AzCD results suggested that the cavity of )5-CD can include more 

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