宽带光诱导 [2+2] 循环添加和热诱导循环逆转驱动的动态分子晶体
Jiangbin Zhong1, Jingbo Sun1, Chao Chen1
1Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130021, P. R. China.
Angewandte Chemie (International ed. in English)
|February 10, 2025
概括
动态分子晶体通过 [2+2] 循环添加利用可见光进行机械工作. 这一过程将能量存储在紧张的纽带中,从而使热能触发的可逆执行成为可能,为太阳能驱动的执行器铺平了道路.
科学领域:
- 材料科学 材料科学 材料科学
- 摄影化学的使用.
- 晶体学 晶体学是指结晶学.
背景情况:
- 光机械响应材料将光转化为机械工作.
- 分子太阳能热能存储 (MOST) 系统正在探索能量转换.
- 固体中的光诱导 [2+2] 循环添加在可逆作用方面尚未得到充分研究.
研究的目的:
- 研究在动态有机晶体中用于储能和激活的宽带光诱导的 [2+2] 循环添加.
- 为了证明可见光作为能量储存和热能释放的触发器.
- 探索 [2+2] 循环加法在开发新型 MOST 架构和晶体执行器方面的潜力.
主要方法:
- 使用了一个原型材料,pyrenylvinylpyrylium tetrafluoroborate (1-PVPyL).
- 用紫外线,绿色,红色和宽带可见光辐射单晶,以诱导拓化学 [2+2] 循环添加.
- 观察到晶体曲 (启动) 和热循环逆转以释放能量.
主要成果:
- 证明 1-PVPyL 在用可见光 (532 nm, 620 nm,宽带) 照射时经历 [2+2] 循环添加.
- 观察到单晶转化为单晶 (SCSC),导致晶体曲.
- 展示了可逆执行,储存的能量通过热循环逆转释放.
结论:
- 宽带可见光可以诱导 [2+2] 循环添加用于动态有机晶体的能量存储和激活.
- [2+2]循环添加反应为开发新的MOST系统和可见光驱动的晶体执行器提供了潜力.
- 这种方法为机械应用利用太阳能提供了一个多功能平台.
相关概念视频
Cycloaddition Reactions: MO Requirements for Thermal Activation
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Thermal cycloadditions are reactions where the source of activation energy needed to initiate the reaction is provided in the form of heat. A typical example of a thermally-allowed cycloaddition is the Diels–Alder reaction, which is a [4 + 2] cycloaddition. In contrast, a [2 + 2] cycloaddition is thermally forbidden.
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Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
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