Professor Weizhi Wang in Fudan University published a new paper entitled “Graphene-like Molecules Based on Tetraphenylethene Oligomers: Synthesis, Characterization, and Applications” in Chemistry of Materials on 30 June 2014.

In this paper, graphene-like molecules were prepared by oxidative cyclodehydrogenation of tetraphenylethene oligomers using iron (III) chloride as the catalyst under mild conditions. All the oxidized samples can be separated effectively from the stepwise ring-closing reaction that highly related to the reaction time. Interestingly, we successfully obtained a series of colorful luminogens with blue, cyan and green-emission during this stepwise and accurate ring closing process, as shown in Figure 1.

Figure 1. Oxidation of compound 4 in a stepwise process.

For the strong intermolecular interaction, our graphene molecules can self-assemble to form a red-colored and hexagonal fibre. Furthermore, some molecules exhibit piezochromic luminescence. The PL emission of the molecules before and after oxidation can be dramatically quenched by picric acid through the electron transfer and/or energy transfer mechanism, enabling them to function as chemosensors for explosive detection. In addition, fluorescence cell imaging studies proved their potential biological application.

More information: http://pubs.acs.org/doi/abs/10.1021/cm501590w