Cyclodextrin nanosponge-sensitized enantiodifferentiating photoisomerization of cyclooctene and 1,3-cyclooctadiene
نویسندگان
چکیده
Enantiodifferentiating geometrical photoisomerizations of (Z)-cyclooctene and (Z,Z)-1,3-cyclooctadiene were performed by using the pyromellitate-linked cyclodextrin network polymer, termed "cyclodextrin nanosponge (CDNS)", as a supramolecular sensitizing host. The photochirogenic behavior of the nanosponges incorporating β- or γ-cyclodextrin was significantly different from that reported for the conventional sensitizer-appended monomeric cyclodextrins, affording chiral (E)-cyclooctene and (E,Z)-cyclooctadiene in enantiomeric excesses critically dependent on the solution pH and solvent composition employed, revealing the active roles of chiral void spaces of CDNS in the photochirogenic reaction.
منابع مشابه
Phase-controlled supramolecular photochirogenesis in cyclodextrin nanosponges.
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 corresp...
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