Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
593981 | Colloids and Surfaces A: Physicochemical and Engineering Aspects | 2012 | 5 Pages |
This paper describes an interesting structure dependent thermo-reversible dissolution of organic molecules in the presence of β-cyclodextrin (β-CD) in N, N-dimethyllformamide (DMF). β-CD could influence the solubility of dissolved organic molecules, resulting in the precipitation of organic molecule–β-CD complex from the original transparent solution as the temperature is increasing, while the precipitate will be dissolved again upon cooling. Different organic molecule–β-CD complex precipitates corresponded to different turbid temperatures (Tt). No precipitates were observed solely for either organic molecules or β-CD in DMF when the temperature increased, indicating the structure dependent recognition of β-CD to organic molecules. This molecular recognition behavior had been successfully applied in the separation of xylene isomers in preparative scale.
Graphical abstractVarieties of small organic molecules can be precipitated in DMF by β-CD in the form of inclusion complex at different temperatures by a molecular recognition thermo-reversible process. The finding was successfully applied for the separation of xylene isomer mixtures in a preparation-scale in DMF solution.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► An unusual structure dependent thermo-reversible precipitation–dissolution behavior was reported. ► Varieties of small organic molecules could be precipitated/dissolved in the presence of β-CD by heating/cooling in DMF. ► They can form organic molecules–β-CD complex by heating. ► Different organic molecule–β-CD complex precipitates corresponded to different temperature. ► This behavior was successfully applied for the separation of xylene isomer mixtures in DMF solution.