Phenolate and phenoxyl radical complexes of Cu(II) and Co(III), bearing a new redox active N,O-phenol-pyrazole ligand.
Phenolate and phenoxyl radical complexes of Cu(II) and Co(III), bearing a new redox active N,O-phenol-pyrazole ligand.
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Cu(II) 和 Co(III) 的酚盐和苯氧基自由基配合物，带有新的氧化还原活性 N,O-苯酚-吡唑配体。
DOI：
10.1039/c1dt10615e
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发表时间：
2011
影响因子：
4
通讯作者：
L. Bénisvy
中科院分区：
文献类型：
--
作者：
Galina M. Zats;H. Arora;R. Lavi;D. Yufit;L. Bénisvy
本文报道了新型 N,O-苯酚-吡唑前配体 (pz)LH 的合成和表征，该新型 N,O-苯酚-吡唑前配体 (pz)LH 包含与邻，对二叔丁基取代苯酚共价连接的吡唑。在室温下的 CH(2)Cl(2) 中，(pz)LH 的循环伏安图 (CV) 表现出准可逆的单电子氧化过程（E(1/2) = 0.66 V vs. Fc(+)/Fc），归因于苯氧基自由基阳离子 [(pz)LH]˙(+) 的形成。 (pz)LH 与 M(II)(BF(4))(2) (M = Cu, Co) 以 2:1 的比例反应，分别生成双-Cu(pz)L(2) (1) 和三-Co(pz)L(3) (2) 配合物。 1的X射线结构揭示了在方形平面反式-Cu(II)-N(2)O(2)配位环境中的Cu(II)离子，而2的X射线结构由具有八面体mer-N(3)O(3)配位球的Co(III)离子组成；由两个（在1中）或三个（在2中）N,O-二齿酚盐配体分别螯合形成。 NMR（2）和EPR（1）数据显示，两种结构均保留在CH(2)Cl(2) 溶液中。 1和2的CV分别由两个（E(1/2)：0.43和0.58 V vs. Fc(+)/Fc)和三个(E(1/2) = 0.12、0.54和0.89 V vs. Fc(+)/Fc)可逆单电子氧化过程组成。 1 和 2 的单电子电化学氧化产生氧化物质 1(+) 和 2(+)，它们在室温惰性气氛 CH(2)Cl(2) 中可稳定数小时。 1(+) 和 2(+) 获得的 UV/vis 和 EPR 数据与后者被配制为 Cu(II)- 和 Co(III)-苯氧基自由基配合物，分别为 [Cu(II)((pz)L˙)((pz)L)](+) 和 [Co(III)((pz)L˙)((pz)L)(2)](+) 明确一致。
The synthesis and characterisation of the new N,O-phenol-pyrazole pro-ligand, (pz)LH, comprising a pyrazole covalently linked to an o,p-di-tert-butyl-substituted phenol, are herein reported. In CH(2)Cl(2) at room temperature, the cyclic voltammogram (CV) of (pz)LH exhibits a quasi-reversible one-electron oxidation process (at E(1/2) = 0.66 V vs. Fc(+)/Fc) attributed to the formation of the phenoxyl radical cation [(pz)LH]˙(+). (pz)LH reacts with M(II)(BF(4))(2) (M = Cu, Co) in a 2:1 ratio to afford the bis-Cu(pz)L(2) (1) and tris-Co(pz)L(3) (2) complexes respectively. The X-ray structure of 1 reveals a Cu(II) ion in a square-planar trans-Cu(II)-N(2)O(2) coordination environment whereas that of 2 consists of a Co(III) ion with an octahedral mer-N(3)O(3) coordination sphere; formed by the chelation of two (in 1) or three (in 2) N,O-bidentate phenolate ligands respectively. Both structures are preserved in CH(2)Cl(2) solution, as revealed by their NMR (for 2) and EPR (for 1) data. The CVs of 1 and 2 consist of two (at E(1/2): 0.43 and 0.58 V vs. Fc(+)/Fc) and three (E(1/2) = 0.12, 0.54 and 0.89 V vs. Fc(+)/Fc) reversible one-electron oxidation processes, respectively. The one-electron electrochemical oxidation of 1 and 2 produces the oxidised species, 1(+) and 2(+), which are stable for several hours at room temperature under inert atmosphere in CH(2)Cl(2). The UV/vis and EPR data obtained for 1(+) and 2(+) are unambiguously consistent with the latter being formulated as Cu(II)- and Co(III)-phenoxyl radical complexes, as [Cu(II)((pz)L˙)((pz)L)](+) and [Co(III)((pz)L˙)((pz)L)(2)](+) respectively.
影响因子：
62.1
作者：
Warren, Jeffrey J.;Tronic, Tristan A.;Mayer, James M.
通讯作者：
Mayer, James M.