Phase-controlled supramolecular photochirogenesis in cyclodextrin nanosponges
Wenting Liang1, Cheng Yang, Dayang Zhou
1College of Chemistry, Sichuan University, Chengdu 610064, PR China.
Chemical Communications (Cambridge, England)
|February 26, 2013
Abstract:
Pyromellitate-bridged cyclodextrin nanosponges (CDNSs) evolved from sol into gel state upon gradual increase of the concentration from 0.2 to 2000 mg mL(-1) in water. The enantiodifferentiating geometrical photoisomerizations of (Z)-cyclooctene and (Z,Z)-1,3-cyclooctadiene sensitized by CDNS at various concentrations were critically affected by the phase transition of CDNS to afford the corresponding (E)- and (E,Z)-isomers in the highest enantiomeric excesses in the gel state.
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