Structural systematics for o-C6H4XY ligands with X,Y= O, NH, and S donor atoms.: o-Iminoquinone and o-iminothioquinone complexes of ruthenium and osmium
Structural systematics for o-C6H4XY ligands with X,Y= O, NH, and S donor atoms.: o-Iminoquinone and o-iminothioquinone complexes of ruthenium and osmium
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DOI：
10.1021/ic025766
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发表时间：
2002-11-04
影响因子：
4.6
通讯作者：
Pierpont, CG
中科院分区：
文献类型：
--
作者：
Bhattacharya, S;Gupta, P;Pierpont, CG
醌配体的结构特征是电荷的特征。邻苯醌、半醌基和儿茶酚电子形式具有C-O键长和环C-C键长模式，其指向特定的配位模式。这种配体电荷和结构之间的相关性已扩展到亚氨基醌和亚氨基硫代醌配体，给出了氧化还原活性金属离子络合物的电子结构的电荷局部化视图。已发现这些配体的自由基半醌形式是令人惊讶的常见配位模式;然而，自由基配体的顺磁性特征在含有顺磁性金属离子的络合物中常常被掩盖。本文报道了Is-d（5）Ru（III）的抗磁性亚氨基半醌（isq）和亚氨基硫代半醌（itsq）配合物及其相应的锇配合物。与锇一起，形成Os（IV）-amidophenolate（ap）氧化还原异构体。研究了Ru（PPh 3）（2）（isq）Cl-2、Ru（PPh 3）（2）（itsq）Cl-2、Os（PPh 3）（2）（ap）Br-2、Os（PPh 3）（2）（atp）Br-2和Os（PPh 3）2（ap）H-2的电化学和光谱性质。Ru（PPh 3）（2）（isq）Cl-2、Ru（PPh 3）（2）（itsq）Cl-2和Os（PPh 3）（2）（ap）H-2的晶体学表征用于分配电荷分布。
The structural features of quinone ligands are diagnostic of charge. The o-benzoquinone, radical semiquinonate, and catecholate electronic forms have C-O bond lengths and a pattern of ring C-C bond lengths that point to a specific mode of coordination. This correlation between ligand charge and structure has been extended to iminoquinone and iminothioquinone ligands, giving a charge-localized view of electronic structure for complexes of redox-active metal ions. The radical semiquinonate form of these ligands has been found to be a surprisingly common mode of coordination; however, the paramagnetic character of the radical ligand is often obscured in complexes containing paramagnetic metal ions. In this report, diamagnetic iminosemiquinonate (isq) and iminothiosemiquinonate (itsq) complexes of Is-d(5) Ru(III) with related complexes of osmium are reported. With osmium, the Os(IV)-amidophenolate (ap) redox isomer is formed. Electrochemical and spectral properties are described for Ru(PPh3)(2)(isq)Cl-2, Ru(PPh3)(2)(itsq)Cl-2, Os(PPh3)(2)(ap)Br-2, Os(PPh3)(2)(atp)Br-2, and Os(PPh3)2(ap)H-2. Crystallographic characterization of Ru(PPh3)(2)(isq)Cl-2, Ru(PPh3)(2)(itsq)Cl-2, and Os(PPh3)(2)(ap)H-2 was used to assign charge distributions.