Cyclodextrin-catalyzed self-assembly of a coordinating fluorescent molecule into microflowers.

We report that γ-cyclodextrin (γ-CD) is able to catalyze the self-assembly process of the coordinating fluorescent molecule pyrenebutyrate with Zn 2+ . The direct interaction between pyrenebutyrate and Zn 2+ would simply lead to amorphous precipitates, whereas addition of Zn 2+ to the host-guest complex of pyrenebutyrate @ γ-CD would generate well-defined microflowers that have exactly the same composition as the amorphous pyrenebutyrate/Zn 2+ . The evidence of host-guest formation between 1-PBA and γ-CD and the absence of γ-CD in the final microflowers manifest that γ-CD acts as a catalyst in the self-assembly process. We envision that this dynamic host-guest chemistry would be very promising in creating catassemblies.