Thermoresponsive Corannulene

We demonstrate herein that corannulene, a bowl-shaped polycyclic aromatic hydrocarbon, can assemble into larger supramolecular structures in water through a change in the solution temperature. This property is invoked through a simple five-fold symmetric substitution of the corannulene nucleus with triethylene glycol units. Interestingly, an increase in the solution temperature, which triggers the assembly process, also enhances the fluorescence emission properties of the assembled materials. Although the emission remains very weak in solution, bright green luminescence can be observed in the fibrilar form. This unexpected and interesting behavior indicates that the corannulene nucleus presents a new motif for the design of aggregation-induced emission (AIE) based luminogens. To the best of our knowledge, this is the first report of a thermoresponsive nonplanar polycyclic hydrocarbon derivative that can respond to a thermal trigger and assemble into larger emissive structures.