Kelbysheva Elena S, Ezernitskaya Mariam G, Aysin Rinat R, Strelkova Tatyana V, Rodionov Alexey N, Telegina Lyudmila N
A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilova 28, Moscow 119991, Russia.
Molecules. 2023 Oct 15;28(20):7098. doi: 10.3390/molecules28207098.
Photochemical properties of symmetrical pyromellitic diimide containing two cymantrenyl fragments at two nitrogen atoms were studied with IR, NMR, UV-vis, ESI-MS, and cyclic voltammetry. It was found that new unstable chelates are formed during photolysis. At the same time, the CO ligand dissociates from two Mn(CO) fragments during photoexcitation, which dramatically changes the electronic and redox properties of the molecule compared to the cymantrene derivative containing one imide fragment. Photolysis leads to a color change from light yellow to green. DFT calculations confirmed the possibility of the formation of complexes due to the loss of one or two CO ligands from manganese atoms. The results obtained with variation of photolysis conditions demonstrated the hemilabile character of the Mn-O=C(imide) bond. On addition of external ligands, the color and electrochemical properties changed, which is promising for the use of this complex as a sensor for small molecules.
通过红外光谱（IR）、核磁共振（NMR）、紫外可见光谱（UV-vis）、电喷雾电离质谱（ESI-MS）和循环伏安法研究了在两个氮原子处含有两个环戊二烯基锰片段的对称均苯四甲酸二酰亚胺的光化学性质。研究发现，在光解过程中会形成新的不稳定螯合物。同时，在光激发过程中，CO配体从两个Mn(CO)片段上解离，与含有一个酰亚胺片段的环戊二烯基锰衍生物相比，这极大地改变了分子的电子和氧化还原性质。光解导致颜色从浅黄色变为绿色。密度泛函理论（DFT）计算证实了由于锰原子失去一个或两个CO配体而形成配合物的可能性。在改变光解条件下获得的结果表明了Mn-O=C(酰亚胺)键的半不稳定性质。加入外部配体后，颜色和电化学性质发生了变化，这使得该配合物有望用作小分子传感器。
