Synthesis, Characterization, and Properties of Iron(II) Spin-Crossover Molecular Photoswitches Functioning at Room Temperature.
Synthesis, Characterization, and Properties of Iron(II) Spin-Crossover Molecular Photoswitches Functioning at Room Temperature.
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DOI：
10.1021/acs.inorgchem.7b01952
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发表时间：
2017-10
影响因子：
4.6
通讯作者：
Max Mörtel;Alexander Witt;F. Heinemann;S. Bochmann;J. Bachmann;Marat M. Khusniyarov
中科院分区：
文献类型：
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作者：
Max Mörtel;Alexander Witt;F. Heinemann;S. Bochmann;J. Bachmann;Marat M. Khusniyarov
合成了自旋交叉分子开关[Fe II（H2 B（pz）2）2L]（L =具有光致变色二芳基乙烯单元的新型邻菲咯啉配体; pz = 1-吡唑基），并通过变温X射线晶体学、穆斯堡尔谱和磁性测量进行了全面表征。详细研究了引入邻菲咯啉骨架（L2）和光致变色二芳基乙烯单元（L3）的取代基对无金属配体和自旋交叉铁（II）配合物2和3的光物理性质的影响。在室温下，配体和配合物都可以在溶液中用光进行转换。2的光环化伴随着在19%下测定的高自旋到低自旋的光转化。L3和3的闭环异构体揭示了在几分钟范围内的寿命，而L2和2的闭环异构体在室温下的溶液中热稳定数天。光开关的可逆性可以通过避免光稳态来改善。前瞻性地引入锚定基团的菲咯啉骨干可能会允许化学吸附的自旋交叉物种的自组装单分子膜的结构在室温下与光切换。
Spin-crossover molecular switches [FeII(H2B(pz)2)2L] (L = novel phenanthroline-based ligands featuring photochromic diarylethene units; pz = 1-pyrazolyl) were synthesized and thoroughly characterized by variable-temperature X-ray crystallography, Mössbauer spectroscopy, and magnetic measurements. The effect of substituents introduced into the phenanthroline backbone (L2) and into the photochromic diarylethene unit (L3) on photophysical properties of metal-free ligands and spin-crossover iron(II) complexes 2 and 3, respectively, were investigated in detail. Both ligands and complexes could be switched with light in solution at room temperature. The photocyclization of 2 was accompanied by a high-spin to low-spin photoconversion determined at 19%. The closed-ring isomers of L3 and 3 reveal the lifetimes in the range of minutes, whereas those of L2 and 2 are thermally stable for days in solutions at room temperature. The reversibility of the photoswitching can be improved by avoiding the photostationary states. Prospective introduction of anchoring groups to the phenanthroline backbone might allow the construction of chemisorbed self-assembled monolayers of spin-crossover species switchable with light at room temperature.