Development of a Novel D–π–A Mechanochromic Luminescent AIEgen for Multifunctional Applications

Abstract Despite recent extensive studies on mechanochromic luminescence (MCL), rational crafting of new facilely obtainable multifunctional luminescent (MFL) materials from the simple AIEgen skeleton that remain a great challenge due to the impact of the undesirable concentration quenching effect. In this study, we have precisely designed and synthesized a novel donor ( D )‐π‐acceptor (A) type of AIE fluorophore (RFTP) by adding one tetraphenylethylene (TPE) unit as a rotator unit to the rofecoxib skeleton by one facile step reaction. RFTP showed a clear mechanochromic behaviors, accompanied by a redshift of 74 nm. In addition, powder X‐ray diffraction (PXRD) and differential scanning calorimetry (DSC) curves indicated the reversible mechanochromic process of RFTP that was caused by the effective phase transition from crystalline state to an amorphous state. Furthermore, RFTP displayed a good optical properties including a large Stokes shift (252 nm) and a typical AIE properties. Meanwhile, density functional theory (DFT) theoretical results support that larger conjugation in RFTP may be the reason for red emissive fluorescence. RFTP can also be effectively localize lipid droplets, positioning it as a useful fluorescent probe for monitoring lipid metabolism in living cells. Taken together, we can provide an efficient strategy to obtain new AIEgens for developing promising multifunctional materials.