Department of Chemistry , The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong , China.
Department of Chemistry , The Chinese University of Hong Kong , Shatin, New Territories, Hong Kong , China.
Inorg Chem. 2018 Aug 6;57(15):9215-9222. doi: 10.1021/acs.inorgchem.8b01229. Epub 2018 Jul 11.
Dinuclear iron nitrido phthalocyanine complexes are of interest owing to their applications in catalytic oxidation of hydrocarbons. While nitrido-bridged diiron phthalocyanine complexes are well documented, the oxidation chemistry of heterodinuclear iron(IV) phthalocyanine nitrides has not been well explored. In this paper we report on the synthesis of a heterometallic Fe/Ru phthalocyanine nitride and its oxidation to yield phthalocyanine cation radical and hydroxyphthalocyanine complexes. Treatment of [Fe(Pc)] (Pc = phthalocyanine dianion) with [Ru(L)(N)Cl] (L = [Co(η-CH){P(O)(OEt)}]) (1) afforded the heterometallic μ-nitrido complex [Cl(L)Ru(μ-N)Fe(Pc)(HO)] (2) that contains an Ru=N = Fe linkage with the Ru-N and Fe-N distances of 1.689(6) and 1.677(6) Å, respectively, and Ru-N-Fe angle of 176.0(4)°. Substitution of 2 with 4- tert-butylpyridine (Bupy) gave [Cl(L)Ru(μ-N)Fe(Pc)(Bupy)]. The cyclic voltammogram of 2 displayed a reversible Pc-centered oxidation couple at +0.18 V versus Fc (Fc = ferrocene). The oxidation of 2 with [N(4-BrCH)]SbCl led to isolation of the cationic complex [Cl(L)Ru(μ-N)Fe(Pc)(HO)][SbCl][SbCl(OH)] (2[SbCl][SbCl(OH)]), whereas that with PhICl yielded the chloride complex [Cl(L)Ru(μ-N)Fe(Pc)Cl] (3). Complexes 2[SbCl][SbCl(OH)] and 3 have been characterized by X-ray crystallography. The UV/visible spectra of 2 (λ = 515 and 747 nm) and 3 (λ = 506 and 748 nm) displayed absorption bands that are characteristic of Pc cation radical. The EPR spectrum of 3 showed a signal with the g value of 2.0012 (width = 5 G) that is consistent with an organic radical. The spectroscopic data support the formulation of 2 and 3 as Ru-Fe Pc cation radical complexes. The reaction of 2 with PhI(CFCO) in dried CHCl afforded a mixture of [Cl(L)Ru(μ-N)Fe(Pc)(CFCO)] (4) and a hydroxyphthalocyanine complex, Cl(L)Ru(μ-N)Fe(Pc-OH)(HO) (5), whereas that in wet CHCl (containing ca. 0.5% water) led to isolation of 5 as the sole product. Complex 4 was independently prepared by salt metathesis of 3 with AgCFCO.
双核铁亚硝酞菁配合物因其在催化氧化烃类方面的应用而受到关注。虽然亚硝桥联二铁酞菁配合物已有很好的文献记载，但异核双核铁（IV）亚硝酞菁配合物的氧化化学尚未得到很好的探索。在本文中，我们报告了一种杂金属 Fe/Ru 酞菁亚硝化物的合成及其氧化为酞菁阳离子自由基和羟基酞菁配合物。用 [Ru(L)(N)Cl]（L = [Co(η-CH){P(O)(OEt)}]）（1）处理 [Fe(Pc)]（Pc = 酞菁二阴离子）得到了含有 Ru=N = Fe 键的杂核 μ-亚硝化物配合物 [Cl(L)Ru(μ-N)Fe(Pc)(HO)]（2），其中 Ru-N 和 Fe-N 的距离分别为 1.689（6）和 1.677（6）Å，Ru-N-Fe 角为 176.0（4）°。用 4-叔丁基吡啶（Bupy）取代 2 得到了 [Cl(L)Ru(μ-N)Fe(Pc)(Bupy)]。2 的循环伏安图显示出在相对于 Fc（Fc = 二茂铁）为+0.18 V 的可逆 Pc 中心氧化偶对。用 [N(4-BrCH)]SbCl 氧化 2 得到了阳离子配合物 [Cl(L)Ru(μ-N)Fe(Pc)(HO)][SbCl][SbCl(OH)]（2[SbCl][SbCl(OH)]），而用 PhICl 则得到了氯化物配合物 [Cl(L)Ru(μ-N)Fe(Pc)Cl]（3）。配合物 2[SbCl][SbCl(OH)]和 3 已通过 X 射线晶体学进行了表征。2（λ = 515 和 747 nm）和 3（λ = 506 和 748 nm）的紫外/可见光谱显示出特征为 Pc 阳离子自由基的吸收带。3 的 EPR 谱显示出一个 g 值为 2.0012（宽度= 5 G）的信号，这与有机自由基一致。光谱数据支持 2 和 3 作为 Ru-Fe Pc 阳离子自由基配合物的配方。2 与 PhI(CFCO)在干燥的 CHCl 中的反应得到了 [Cl(L)Ru(μ-N)Fe(Pc)(CFCO)]（4）和一种羟基酞菁配合物 Cl(L)Ru(μ-N)Fe(Pc-OH)(HO)（5）的混合物，而在含有约 0.5%水的湿 CHCl 中的反应则得到了 5 作为唯一产物。配合物 4 可以通过 3 与 AgCFCO 的盐交换反应独立制备。
