2044-73-7Relevant articles and documents
Spin Crossover vs. High-Spin Iron(II) Complexes in N4S2 Coordination Sphere Containing Picolyl-Thioether Ligands and NCE (E=S, Se and BH3) Co-Ligands
Plaza-Lozano, Diego,Conde-Gallardo, Agustín,Olguín, Juan
, p. 2846 - 2856 (2021)
To study the effect of the chelate ring size on the magnetic properties of thioether-based iron(II) metal complexes, two ligands have been envisaged, synthesised and characterised. The two ligands correspond to the bidentate benzylpicolylthioether (PySBn) and tetradentate 2,3-bis(((2-pyridylmethyl)thio)methyl)quinoxaline (QuinoxS). Five iron(II) complexes have been synthesised, containing either two bidentate ligands or one tetradentate ligand, and two N-bond NCE co-ligands (E=S, Se or BH3): trans-[FeII(PySBn)2(NCE)2] (1 a–b) and cis-[FeII(QuinoxS)(NCE)2] (2 a–c), a for E=S, b for E=Se and c for E=BH3. The iron(II) complexes have been characterised by standard techniques, X-ray crystallography (except for complex 1 a) and VT-magnetic measurements in the solid state. X-ray crystallography showed that all the complexes are isolated in the high spin (HS) state, based on the relatively long Fe?L bond lengths, Fe?N>2.0 ? and Fe?S≈2.5–2.6 ?. VT-magnetic measurements demonstrated that complexes 1 a and 2 a-c are stabilised in the HS-state, showing orbital contribution to g and zero field splitting. However, complexes 1 b shows a relatively abrupt, hysteretic, and incomplete at the low-end spin conversion, with T1/2↓=92, T1/2↑=98 K and ΔT1/2=6 K at 5 K min?1, moreover, the hysteresis loop is scan rate dependent increasing up to 11 K at 10 K min?1. An analysis of structural and electronic parameters has been performed to rationalise the differing magnetic properties of the metal complexes, such as metallacycle size, bond lengths and angles, and cis- vs. trans-coordination mode. A comparison with the literature-reported spin crossover iron(II) complexes in N4S2 coordination sphere containing NCE co-ligands has been conducted as well, finding that, as previously reported, the Fe?N?C(E) bond angle is diagnostic for determining the spin lability of the metal complexes, and in addition we have found that the N?C(E) bond length is too useful.
Fluorescent molecule for recognizing copper ions, preparation method and application
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Paragraph 0099; 0108; 0109; 0110, (2019/02/04)
The invention discloses a fluorescent molecule for recognizing copper ions, a preparation method and application. Polycyclic aromatic hydrocarbons such as naphthalene rings or anthracene rings are used as initial raw materials; through a series of optimized organic synthesis reaction (substitution and addition), after the connection with different recognition sites, molecular clamp body tweezer host compounds with different recognition performance can be obtained. The fluorescent molecule can be used for copper ion detection and solves the problems that the existing molecule device is difficult to effectively recognize object molecules.
The reactions of pyridinyl thioesters with triiron dodecacarbonyl: Their novel diiron carbonyl complexes and mechanistic investigations
Long, Li,Xiao, Zhiyin,Zampella, Giuseppe,Wei, Zhenhong,De Gioia, Luca,Liu, Xiaoming
, p. 9482 - 9492 (2012/09/05)
Reaction of Fe3(CO)12 with pyridinyl thioester ligand PyCH2SCOCH3 (L1, Py = pyridin-2-yl) produced complex, [Fe2(κ-COCH3)(μ-SCH2Py)(CO) 5] (1) (PyCH2S = pyridin-2-ylmethanethiolate). When complex 1 reacted with PPh3, a monosubstituted complex, [Fe 2(κ-COCH3)(μ-SCH2Py)(CO) 4PPh3] (2), was derived. Reaction of the same precursor with analogous thioester ligand PyCH2SCOPy (L2) generated three novel diiron complexes, [Fe2(κ-Py)(μ-SCH 2Py)(CO)5] (3), [Fe2(κ-Py)′(μ- SCH2Py)(CO)5] (4), and [Fe2(κ-Py)(μ- SCH2Py)(CO)6] (5). Complexes 3 and 4 are structural isomers. Complex 5 could be converted into complex 4 but the conversion from complex 5 to the isomer 3 was not observed. All the five complexes were fully characterised using FTIR, NMR, and other techniques. Their structures were determined using X-ray single crystal diffraction analysis. The oxidative formation of complexes 1, 3, 4, and 5 involved C-S and/or C-C bonds cleavages. To probe possible mechanisms for these cleavages, DFT calculations were performed. From the calculations, viable reaction pathways leading to the formation of all the isolated products were delineated. The results of the theoretic calculations also allowed rationalisation of the experimental observations.
