Telluracarbaporphyrins and a Related Palladium(II) Complex: Evidence for Hypervalent Interactions
Telluracarbaporphyrins and a Related Palladium(II) Complex: Evidence for Hypervalent Interactions
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DOI：
10.1021/acs.inorgchem.1c01039
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发表时间：
2021-06-17
影响因子：
4.6
通讯作者：
Ferrence, Gregory M.
中科院分区：
文献类型：
--
作者：
Lash, Timothy D.;AbuSalim, Deyaa, I;Ferrence, Gregory M.
卡巴三吡林与碲苯二甲醇在 BF3 中心点 Et2O 存在下反应，然后用 DDQ 氧化，得到碲碳卟啉的第一个例子。尽管该系统表现出强烈的芳香特征，但它易于空气氧化，产生通过 X 射线晶体学表征的羟基衍生物。最初的碲碳卟啉与乙酸钯(II)反应生成稳定的有机金属配合物，X射线晶体学表明钯阳离子与CNTeN核中的所有四个原子配位。奥沙卡巴三吡林还与碲苯二醇反应，得到具有 CNTeO 核的空气稳定的卟啉类似物。非金属化碲碳卟啉表现出相对较短的 Te-N 分离，这强烈暗示了高价碲相互作用的参与。此外，尽管存在非常大的碲原子，碲芬亚基并没有像在没有这些相互作用的情况下所预期的那样强烈地远离平均大环平面。通过质子核磁共振波谱、NICS 计算和 AICD 图评估了杂碳卟啉的芳香性质。此外，还研究了羟基碲卟啉与其氧化碲酚互变异构体相比的相对稳定性，并评估了这些氧化结构的芳香特征。
The reaction of a carbatripyrrin with a tellurophene dicarbinol in the presence of BF3 center dot Et2O, followed by oxidation with DDQ, afforded the first example of a telluracarbaporphyrin. Although this system exhibits strongly aromatic characteristics, it is prone to air oxidation, giving rise to a hydroxy derivative that was characterized by X-ray crystallography. The initial telluracarbaporphyrin reacted with palladium(II) acetate to give a stable organometallic complex, and X-ray crystallography showed that the palladium cation was coordinated to all four atoms in the CNTeN core. An oxacarbatripyrrin was also reacted with a tellurophene dialcohol to give an air-stable porphyrin analogue with a CNTeO core. Nonmetalated telluracarbaporphyrins showed relatively short Te-N separations that strongly implied the involvement of hypervalent tellurium interactions. Furthermore, despite the presence of a very large tellurium atom, the tellurophene subunit is not strongly pivoted away from the mean macrocyclic plane as would be expected in the absence of these interactions. The aromatic properties of heterocarbaporphyrins were assessed by proton NMR spectroscopy, NICS calculations, and AICD plots. In addition, the relative stability of hydroxytelluraporphyrins in comparison to their tellurophene oxide tautomers was investigated and the aromatic characteristics of these oxidized structures were evaluated.