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

We report that gamma-cyclodextrin (gamma-CD) is able to catalyze the self-assembly process of the coordinating fluorescent molecule pyrenebutyrate with Zn2+. The direct interaction between pyrenebutyrate and Zn2+ would simply lead to amorphous precipitates, whereas addition of Zn2+ to the host-guest complex of pyrenebutyrate @ gamma-CD would generate well-defined microflowers that have exactly the same composition as the amorphous pyrenebutyrate/Zn2+. The evidence of host-guest formation between 1-PBA and gamma-CD and the absence of gamma-CD in the final microflowers manifest that gamma-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.

Automated summary

We report that gamma-cyclodextrin (gamma-CD) catalyzes the self-assembly of pyrenebutyrate with Zn2+. The addition of Zn2+ to the host-guest complex of pyrenebutyrate and gamma-CD generates well-defined microflowers with the same composition as the amorphous pyrenebutyrate/Zn2+. This suggests that gamma-CD acts as a catalyst in the self-assembly process.