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通过近红外光可切换的捐赠-接受二烯

Kristin Klaue¹, Wenjie Han¹, Pauline Liesfeld¹

¹Department of Chemistry & IRIS Adlershof, Humboldt-Universität zu Berlin, Brook-Taylor-Straße 2, 12489 Berlin, Germany.

Journal of the American Chemical Society

|June 2, 2020

概括

研究人员使用二烯开发了新的近红外 (NIR) 分子开关. 这些开关提供了增强的透和减少损坏,使新的光学地址材料成为可能.

科学领域:

有机化学
材料科学
摄影化学

背景情况:

低强度近红外 (NIR) 光为分子开关提供了优势,包括深层组织透和减少辐射损伤.
设计由低能NIR光子激活的可视化系统是一个重大挑战.

研究的目的:

制定直接的一光子NIR光开关的一般设计策略.
合成并研究基于二烯的新型光开关的光热特性.

主要方法:

用对立的供体-受体替代物合成2,7和4,9非替代二烯.
作为替代剂类型,强度,位置和环境极性的函数,对光热特性进行研究.
在深度NIR区域调整激发波长.

主要成果:

在900nm以上实现了最低的光学转换,显著提高了NIR单光子吸收截面 (大小两倍).
在保持循环二烯同位素合理的热稳定性时,最大限度地提高光异构化效率.
可调节的热半衰期从几毫秒到几个小时.

结论:

开发了基于二烯的NIR激活分子开关的成功策略.
合成的光开关具有出色的NIR吸收和可调节的开关特性.
这些发现为非侵入性,可光学定位的材料和系统开辟了道路.

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