Redox switchable 19π and 18π 5,10,20-triaryl-5,15-diazaporphyrinoid–nickel(II) complexes
Redox switchable 19π and 18π 5,10,20-triaryl-5,15-diazaporphyrinoid–nickel(II) complexes
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DOI：
10.1142/s1088424618500529
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发表时间：
2018-07
影响因子：
1.5
通讯作者：
Keisuke Sudoh;Takuroh Hatakeyama;K. Furukawa;H. Nakano;Y. Matano
中科院分区：
文献类型：
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作者：
Keisuke Sudoh;Takuroh Hatakeyama;K. Furukawa;H. Nakano;Y. Matano
报道了镍（II）配合物5,10,20-三芳基-5,15-重氮卟啉（TriADAP）的合成及其光学、电化学和磁性能。不对称取代镍(II) -双（1-氨基-9-氯-5-甲酰基二吡啶；甲酰基= 2,4,6-三甲基苯基）配合物的金属模板环化，根据碱和溶剂的组合，可以得到相应的TriADAPs或5-芳基-15-苄基-10,20-二酰基-5,15-重氮卟啉。后一个大环通过Pd/ c促进氢化对苯基脱保护，转化为TriADAP。TriADAPs在18种[公式：见文]（阳离子）和19种[公式：见文]（中性）形式中均被分离。这两种氧化态之间的相互转换导致DAP体系光学性质的明显变化[公式：见文本]。3 - adap阳离子的核磁共振光谱显示它们具有芳香特征，而3 - adap阳离子的EPR光谱显示它们具有高度离域的电子自旋[公式：见文本]。TriADAPs的芳基的对取代基对其HOMO和LUMO能量有很小但明显的影响。一个电子净电荷的变化直接反映在DAP环的氧化还原性能上；TriADAP比DAP更容易被还原，更不容易被氧化。净电荷的差异也反映在[公式：见文本]氢核磁共振光谱中观察到的吡唑[公式：见文本]-质子的屏蔽上。目前的结果证实，TriADAP是一个非常有前途的框架，用于构建一类新的氮卟啉基材料，具有18[公式：见文]-19[公式：见文]可氧化还原的光学和磁性能。
The synthesis and optical, electrochemical, and magnetic properties of nickel(II) complexes of 5,10,20-triaryl-5,15-diazaporphyrin (TriADAP) are reported. Metal-templated cyclization of unsymmetrically substituted nickel(II)–bis(1-amino-9-chloro-5-mesityldipyrrin; mesityl = 2,4,6-trimethylphenyl) complexes afforded the corresponding TriADAPs or 5-aryl-15-benzyl-10,20-dimesityl-5,15-diazaporphyrin, depending on the combination of base and solvent. The latter macrocycle was converted to TriADAP by deprotection of the [Formula: see text]-benzyl group through Pd/C-promoted hydrogenation. TriADAPs were isolated in both 18[Formula: see text] (cation) and 19[Formula: see text] (neutral) forms. The interconversion between these two oxidation states resulted in a distinct change in the optical properties of the DAP [Formula: see text]-system. NMR spectroscopy of the 18[Formula: see text] TriADAP cations showed that they had aromatic character, whereas EPR spectroscopy of the 19[Formula: see text] TriADAP showed a highly delocalized electron spin of the [Formula: see text]-radical. The para substituents of the [Formula: see text]-aryl groups of TriADAPs had a small but distinct impact on their HOMO and LUMO energies. The change in the net charge of one electron was directly reflected in the redox properties of the DAP ring; TriADAP was more easily reduced and less easily oxidized than DAP. The difference in the net charge was also reflected by the shielding of the pyrrolic [Formula: see text]-protons observed in the [Formula: see text]H NMR spectra. The present results confirm that TriADAP is a highly promising framework for constructing a new class of azaporphyrin-based materials with 18[Formula: see text]–19[Formula: see text] redox-switchable optical and magnetic properties.