Tetraphenylethylene fused pyrrolo[3,2-b]pyrrole derivatives with reversible mechanofluorochromic and aggregation-induced emission enhancement characteristics

Abstract

Modification on typical of molecular unit with aggregation-induced emission (AIE)/aggregation-induced emission enhancement (AIEE) can play a important role in obtaining solid-state fluorescence materials and mechanofluorochromic (MFC) materials. We utilize the multicomponent reaction of TPE-containing aldehyde, arylamine and butane-2,3-dione in the presence of iron(III) perchlorate to design and synthesize two novel MFC materials by combination of the tetraphenylethylene (TPE) and pyrrolo [3,2-b]pyrrole core units. Investigation of CHW-1 and CHW-2 aggregation-induced emission behaviors indicated that these materials all exhibited AIEE properties. Subsequent mechanochromic luminescence tests exhibited reversible mechanochromism natures that involve fluorescent color change from green to yellow (Grinding-induced spectral shift (△λ): 35 nm and 38 nm, respectively). Then the datas (including SEM, PXRD and DSC) revealed that this mechanofluorochromism was ascribed to the transformation of crystal state to the amorphous form. Moreover, CHW-1 and CHW-2 could be applied for optical recording devices and security printing.