Valence-state alternatives in diastereoisomeric complexes [(acac)2Ru(μ-QL)Ru(acac)2]n (QL2-=1,4-dioxido-9,10-anthraquinone, n =+2,+1, 0,-1,-2)

被引：82

作者：

Maji, Somnath ^{[2
]}

Sarkar, Biprajit ^{[3
]}

Mobin, Shaikh M. ^{[2
]}

Fiedler, Jan ^{[4
]}

Urbanos, Francisco A. ^{[1
]}

Jimenez-Aparicio, Reyes ^{[1
]}

Kaim, Wolfgang ^{[3
]}

Lahiri, Goutam Kumar ^{[2
]}

机构：

[1] Univ Complutense, Dept Quim Inorgan, Fac Ciencias Quim, E-28040 Madrid, Spain

[2] Indian Inst Technol, Dept Chem, Bombay 400076, Maharashtra, India

[3] Univ Stuttgart, Inst Anorgan Chem, D-70550 Stuttgart, Germany

[4] Acad Sci Czech Republ, J Heyrovsky Inst Phys Chem, CZ-18223 Prague, Czech Republic

来源：

INORGANIC CHEMISTRY | 2008年 / 47卷 / 12期

关键词：

D O I：

10.1021/ic800115q

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

The title complexes were obtained in neutral form (n = 0) as rac (1) and meso isomers (2). 2 was crystallized for X-ray diffraction and its temperature-dependent magnetism studied. It contains two antiferromagnetically coupled ruthenium(III) ions, bridged by the quinizarine dianion QL(2-) (quinizarine = 1,4-dihydroxy-9, 10-anthraquinone). The potential of both the ligand (QL(0) -> OL4-) and the metal complex fragment combination [(acac)(2)RUII](2) -> {[(acac)(2)Ru-IV](2)}(4+) to exist in five different redox states creates a large variety of combinations, which was assessed for the electrochemically reversibly accessible 2+, 1+, 0, 1-, 2- forms using cyclic voltammetry as well as EPR and UV-vis-NIR spectroelectrochemistry. The results for the two isomers are similar: Oxidation to 1(+) or 2(+) causes the emergence of a near-infrared band (1390 nm), without revealing an EPR response even at 4 K. Reduction to 1(-) or 2(-) produces an EPR signal, signifying metal-centered spin but no near-infrared absorption. Tentatively, we assume metal-based oxidation of [(acac)(2)Ru-II(mu-QL(2-))Ru-III(acac)(2)] to a mixed-valent intermediate [(acac)(2)Ru-III(mu- QL(2-))Ru-IV(acac)(2)](+) and ligand-centered reduction to a radical complex [(acac)(2)Ru-III(mu-QL(3-))Ru-III(acac)(2)](-) with antiferromagnetic three-spin interaction.

引用

页码：5204 / 5211

页数：8

共 126 条

[91] Isovalent and mixed-valent diruthenium complexes [(acac)2RuII (μ-bpytz)RuII(acac)2] and [(acac)2RuII(μ-bpytz)RuIII(acac)2](ClO4) (acac= acetylacetonate and bpytz=3,6-bis(3,5-dimethylpyrazolyi)-1,2,4,5-tetrazine):: Synthesis, spectroelectrochemical, and EPR investigation [J].

Patra, S ;

Sarkar, B ;

Ghumaan, S ;

Fiedler, J ;

Kaim, W ;

Lahiri, GK .

INORGANIC CHEMISTRY, 2004, 43 (19) :6108-6113

[92] {(μ-L)[RuII(acac)2]2}", n = 2+, +, 0, -, 2-, with L=3,3′, 4,4′-tetraimino-3,3′,4,4′-tetrahydrobiphenyl.: EPR- supported assignment of NIR absorptions for the paramagnetic intermediates [J].

Patra, S ;

Sarkar, B ;

Ghumaan, S ;

Fiedler, J ;

Zális, S ;

Kaim, W ;

Lahiri, GK .

DALTON TRANSACTIONS, 2004, (05) :750-753

[93] Separating innocence and non-innocence of ligands and metals in complexes [(L)Ru(acac)2]n (n =-1, 0,+1; L = o-iminoquinone or o-iminothioquinone) [J].

Patra, S ;

Sarkar, B ;

Mobin, SM ;

Kaim, W ;

Lahiri, GK .

INORGANIC CHEMISTRY, 2003, 42 (20) :6469-6473

[94] An unusual dinuclear ruthenium(III) complex with a conjugated bridging ligand derived from cleavage of a 1,4-dihydro-1,2,4,5-tetrazine ring. Synthesis, structure, and UV-vis-NIR spectroelectrochemical characterization of a five-membered redox chain incorporating two mixed-valence states [J].

Patra, S ;

Miller, TA ;

Sarkar, B ;

Niemeyer, M ;

Ward, MD ;

Lahiri, GK .

INORGANIC CHEMISTRY, 2003, 42 (15) :4707-4713

[95] First example of μ3-sulfido bridged mixed-valent triruthenium complex triangle RuIII2RuII(O,O-acetylacetonate)3(μ-O,O,γ-C-acetylacetonate)3(μ3-S) (1) incorporating simultaneous O,O- and γ-C-bonded bridging acetylacetonate units.: Synthesis, crystal structure, and spectral and redox properties [J].

Patra, S ;

Mondal, B ;

Sarkar, B ;

Niemeyer, M ;

Lahiri, GK .

INORGANIC CHEMISTRY, 2003, 42 (04) :1322-1327

[96]

Patra S., 2004, DALTON T, V754

[97] Unique properties of transition metal quinone complexes of the MQ3 series [J].

Pierpont, CG .

COORDINATION CHEMISTRY REVIEWS, 2001, 219 :415-433

[98] THE CHEMISTRY OF TRANSITION-METAL COMPLEXES CONTAINING CATECHOL AND SEMIQUINONE LIGANDS [J].

PIERPONT, CG ;

LANGE, CW .

PROGRESS IN INORGANIC CHEMISTRY, VOL 41, 1994, 41 :331-442

[99] MAGNETIC EXCHANGE INTERACTIONS IN BINUCLEAR TRANSITION-METAL COMPLEXES .18. DIANIONS OF 5,8-DIHYDROXY-1,4-NAPHTHOQUINONE, 1,4-DIHYDROXY-9,10-ANTHRAQUINONE, AND 1,5-DIHYDROXY-9,10-ANTHRAQUINONE AS BRIDGING LIGANDS IN COPPER(II) AND NICKEL(II) COMPLEXES [J].

PIERPONT, CG ;

FRANCESCONI, LC ;

HENDRICKSON, DN .

INORGANIC CHEMISTRY, 1978, 17 (12) :3470-3477

[100] Spin coupling interactions in transition metal complexes containing radical o-semiquinone ligands.: A review [J].

Pierpont, CG ;

Attia, AS .

COLLECTION OF CZECHOSLOVAK CHEMICAL COMMUNICATIONS, 2001, 66 (01) :33-51

← 4 5 6 7 8 9 10 11 12 13 →