Kelly Conor T, Dunne Sean, Kühne Irina A, Barker Andrew, Esien Kane, Felton Solveig, Müller-Bunz Helge, Ortin Yannick, Morgan Grace G
School of Chemistry, University College Dublin, Belfield, Dublin 4, Ireland.
Centre for Nanostructured Media, School of Mathematics and Physics, Queen's University Belfast, BT7 1NN, Belfast, UK.
Angew Chem Int Ed Engl. 2023 Apr 24;62(18):e202217388. doi: 10.1002/anie.202217388. Epub 2023 Mar 24.
Reversible proton-induced spin state switching of an Fe complex in solution is observed at room temperature. A reversible magnetic response was detected in the complex, [Fe (sal 323)]ClO (1), using Evans' method H NMR spectroscopy which indicated cumulative switching from low-spin to high-spin upon addition of one and two equivalents of acid. Infrared spectroscopy suggests a coordination-induced spin state switching (CISSS) effect, whereby protonation displaces the metal-phenoxo donors. The analogous complex, [Fe (4-NEt -sal 323)]ClO (2), with a diethylamino group on the ligand, was used to combine the magnetic change with a colorimetric response. Comparison of the protonation responses of 1 and 2 reveals that the magnetic switching is caused by perturbation of the immediate coordination sphere of the complex. These complexes constitute a new class of analyte sensor which operate by magneto-modulation, and in the case of 2, also yield a colorimetric response.
在室温下观察到溶液中一种铁配合物的质子诱导自旋态可逆切换。使用埃文斯方法的核磁共振光谱在配合物[Fe (sal 323)]ClO（1）中检测到可逆的磁响应，这表明在加入一当量和两当量酸时，自旋态从低自旋累积切换到高自旋。红外光谱表明存在配位诱导自旋态切换（CISSS）效应，即质子化使金属 - 苯氧基供体发生位移。配体上带有二乙氨基的类似配合物[Fe (4 - NEt - sal 323)]ClO（2）用于将磁变化与比色响应相结合。对1和2的质子化响应进行比较表明，磁切换是由配合物紧邻配位球的扰动引起的。这些配合物构成了一类新型的分析物传感器，通过磁调制进行操作，并且对于2来说，还会产生比色响应。
