Anion-tunable configuration isomerism and magnetic coupling in a tetranuclear discrete, one-dimensional (1D) chiral chain and 1D-decker copper(II) complexes of a carbohydrazine derivative.
Anion-tunable configuration isomerism and magnetic coupling in a tetranuclear discrete, one-dimensional (1D) chiral chain and 1D-decker copper(II) complexes of a carbohydrazine derivative.
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DOI：
10.1021/ic4014027
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发表时间：
2014-01
影响因子：
4.6
通讯作者：
Wei Huang;Yuchao Jin;Dayu Wu;Genhua Wu
中科院分区：
文献类型：
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作者：
Wei Huang;Yuchao Jin;Dayu Wu;Genhua Wu
配体N‘-[(pyridin-2-yl)methylene]pyrazine-2-carbohydrazide(Pppcd)与不同的铜盐(1，乙酸盐；2，高氯酸盐；3，硫酸盐)在甲醇中反应，得到一个乙酸桥联的四核离散[Cu2(Ppcd)(Ac)2(H2O)(OH)]2·H2O(1)，一维手性链[Cu(Ppcd)]ClO4(2)，以及三核铜(II)亚单位Cu3(Ppcd)2(H2O)4(SO4)2(3)。单晶X射线分析表明，ppcd配体的构象异构性与-N-N-(反式或顺式)的构型有关，并能在不同阴离子存在下诱导多种配位方式。磁性研究表明，由于构型异构性，化合物1的反铁磁性耦合的大小可以调节[化合物1在室温下实际上是反磁的(J≈-1000 cm(-1))，化合物1在一维均一链中对2具有较强的反铁磁性(J=-255.4 cm(-1))，对三核铜亚单位内的3具有反铁磁性(J=-123.6 cm(-1))。
The reactions of ligand N'-[(pyridin-2-yl)methylene]pyrazine-2-carbohydrazide (ppcd) with different copper salts (1, acetate; 2, perchlorate; 3, sulfate) in MeOH could afford one acetate-bridge tetranuclear discrete [Cu2(ppcd)(ac)2(H2O)(OH)]2·H2O (1), one-dimensional (1D) chiral chain [Cu(ppcd)]ClO4 (2), and a 1D-decker complex of a trinuclear copper(II) subunit, Cu3(ppcd)2(H2O)4(SO4)2 (3). Single-crystal X-ray analysis revealed that conformation isomerism of the ppcd ligand was associated with the configuration of -N-N- (trans or cis) and could induce the versatile coordination mode in the presence of different anions. The 1D chiral chain was interestingly obtained from the achiral rigid ligand in complex 2. Magnetic studies indicated that the magnitude of the antiferromagnetic coupling can be tuned because of the configuration isomerism [compound 1 is practically diamagnetic at room temperature (J ≈ -1000 cm(-1)), with a strong antiferromagnetic one (J = -255.4 cm(-1)) for 2 in the 1D uniform chain and an antiferromagnetic one (J = -123.6 cm(-1)) for 3 within the trinuclear copper subunit].