We synthesized three new benzothiadiazole-cored cyano-substituted diphenylethene derivatives (PT-OMe, PT-H, and PT-CF3) with different methoxy, hydrogen, and trifluoromethyl end groups, and the synthesis confirmed by standard spectroscopic methods. These end groups endowed them with different donorâacceptor (DâA) effects, and they provide them with a peculiar and completely opposite mechanofluorochromic property. Red-shifted mechanofluorochromic features were found in the PT-OMe and PT-H compounds, while on the contrary, PT-CF3 showed blue-shifted mechanofluorochromic behavior. The mechanofluorochromic mechanism was explored and attributed to the metastable state of the ground compounds and the crystalline-amorphous phase transformation between the original and ground states. Moreover, these derivatives showed reversible significant mechanofluorochromic properties and reproducibility between ground and annealed states, making them promising stimuli-responsive and smart luminescent materials for mechanosensors, fluorescence switches and light-emitting device applications. The introduction of the DâA effect strategy demonstrated in this work would provide a new path to fine tune the optical features of mechanofluorochromic materials with unique and diverse fluorescent properties.
我们合成了三种新的苯并
噻二唑芯
氰基取代二苯基
乙烯衍
生物(
PT-OMe、
PT-H 和
PT-
CF3),它们具有不同的甲氧基、氢基和三
氟甲基端基,并通过标准光谱方法证实了合成。这些端基赋予它们不同的供体-受体(DâA)效应,并使它们具有奇特的、完全相反的机械
氟变色特性。在
PT-OMe 和
PT-H 化合物中发现了红移的机械
氟致变色特征,而相反,
PT- 则表现出蓝移的机械
氟致变色行为。研究人员探索了机械
氟致变色的机理,并将其归因于基态化合物的蜕变态以及原始态和基态之间的结晶-非晶相变。此外,这些衍
生物还显示出显著的可逆机械荧光变色特性,以及在基态和退火态之间的可重复性,使它们成为有望应用于机械传感器、荧光开关和发光器件的刺激响应型智能
发光材料。本研究中展示的 DâA 效应策略将为微调具有独特和多样化荧光特性的机械
氟变色材料的光学特性提供一条新的途径。