A New Class of Diarylethene Compounds that Exhibit Turn-On Emission: From Aggregation-Induced Emission to Anti-Kasha Emission

Abstract

Diarylethenes (DAE) are a well-known class of photochromic compounds with diverse applications ranging from optoelectronic devices to biological sensors. DAEs exhibiting emission in the closed form show potential for super-resolution imaging, however, these are rare because DAEs in the closed form are notorious fluorescence quenchers. Here a series of DAE compounds containing phosphine oxide groups is reported that exhibit turn-on emission and are the first examples of DAEs showing both aggregation-induced emission (AIE) and anti-Kasha emission in the closed form. The molecular design of the DAEs originates from careful selection of diphenylphosphine oxide groups, which have the appropriate bulkiness and electron-withdrawing ability. Furthermore, the emission wavelength can be tuned by substituents, leading to a new class of diarylethenes that hold promise for applications including super-resolution imaging.