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‐Diarylpyrazine‐2,5‐dicarboxamido‐Bridged Diruthenium Systems: Structures, Magnetic Properties, and Electronic Forms in Multiredox States
作者:Farheen Fatima Khan、Abhishek Mandal、Johannes Klein、José Luis Priego、Reyes Jiménez‐Aparicio、Biprajit Sarkar、Goutam Kumar Lahiri
DOI:10.1002/ejic.201701009
日期:2017.12.15
Variable-temperature magnetic studies of 1 revealed a weak bridge-mediated intramolecular antiferromagnetic interaction with J = –7.58 cm–1. The dinuclear complexes exhibited anisotropic electron paramagnetic resonance (EPR) signals at g ≈ 2 along with half-field signals at g1/2 ≈ 4, whereas the mononuclear counterpart 3 displayed an EPR signal with rhombic symmetry. Complexes 1 and 2 exhibited two oxidation and reduction
在此,我们报告了由去质子化的 N,N'-二苯基吡嗪-2,5-二甲酰胺 (H2L1) 和 N,N'-dimesitylpyrazine-2,5-二甲酰胺 (H2L2) 配体以内消旋非对映体形式桥接的二钌 (III) 配合物,即 (acac)2RuIII(µ-L1)RuIII(acac)2 (1, acac = 乙酰丙酮) 和 (acac)2RuIII(µ-L2)RuIII(acac)2 (2),以及单去质子化的 HL1 衍生单核对应物 (acac)2RuIII(HL1) (3)。1 的变温磁性研究揭示了一种弱桥介导的分子内反铁磁相互作用,J = –7.58 cm–1。双核配合物在 g ≈ 2 处表现出各向异性电子顺磁共振 (EPR) 信号以及在 g1/2 ≈ 4 处的半场信号,而单核配合物 3 则显示出具有菱形对称性的 EPR 信号。配合物 1 和 2 表现出两个氧化和还原步骤,配比常数 (Kc)