Hierarchical Synthesis, Structure, and Photophysical Properties of Gallium‐ and Ruthenium‐Porphyrins with Axially Bonded Azo Ligands
作者:Yueze Gao、Vroni Walter、Michael J. Ferguson、Rik R. Tykwinski
DOI:10.1002/chem.202002030
日期:2020.12.15
The hierarchical synthesis of three porphyrin and four bisporphyrin derivatives is presented. This strategy relies on the incorporation of linkers based on azo moieties appended with pyridyl and/or acetylenic groups that facilitate axial coordination to Ga‐ and Ru‐metalloporphyrins. These porphyrinic systems allow for a quantitative analysis of the effects of diamagnetic anisotropy (DA) by using 1H NMR
介绍了三种卟啉和四种双卟啉衍生物的分级合成。该策略依赖于结合基于偶氮基的连接基,并附加有吡啶基和/或炔属基团,这些基团有利于Ga-和Ru-金属卟啉的轴向配位。这些卟啉系统可通过1 H NMR光谱和X射线晶体学分析对抗磁各向异性(DA)的影响进行定量分析。实验概述了质子化学位移和与卟啉核的距离之间的简单幂律关系,这证实了先前的理论预测,并表明DA的极限约为2 nm。偶氮连接的卟啉的光物理性质通过紫外/可见光谱分析,表明明显的顺式–仅与Ga卟啉结合的偶氮配体未观察到反式异构化。Ru-卟啉与偶氮配体的结合有利于光开关行为,但该过程面临Ru-卟啉脱羰作用的竞争,只有GaL1Ru记录了明显的开关。