Synthesis, Electronic Structure, and Structural Characterization of the New, “Non-Innocent” 4,5-Dithio-Catecholate Ligand, Its Metal Complexes, and Their Oxidized 4,5-Dithio-o-quino
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- 作者：Dimitri Coucouvanis ; Alok R. Paital ; Qinwei Zhang ; Nicolai Lehnert ; Reinhart Ahlrichs ; Karin Fink ; Dieter Fenske ; Annie K. Powell ; Yanhua Lan
- 刊名：Inorganic Chemistry
- 出版年：2009
- 出版时间：September 21, 2009
- 年：2009
- 卷：48
- 期：18
- 页码：8830-8844
- 全文大小：1175K
- 年卷期：v.48,no.18(September 21, 2009)
- ISSN：1520-510X
文摘
The bifunctional ligand catechol-4,5 dithiol, H2Dtcat, has been synthesized, and the structure of the bis Br− adduct, (HS)2C6H2(OH)2·2Ph4Br·H2O, has been determined. The syntheses, molecular structures, electronic structures, and magnetic properties of the monoanionic [(Dtcat2−)2M]−, (M = Ni, V and M = Cu, VI) complexes have been obtained as Ph4PBr double salts, [M(S2C6H2(OH)2)2][Ph4P]3Br2. These and the antiferromagnetically coupled dimeric [(Dtcat)2Fe][Ph4P]2·4DMF complex, VII, have been structurally characterized. The centrosymmetric [M(S2C6H2(OH)2)2]− complexes in the X-ray isomorphous V and VI are connected via H-bonding to Br− ions to form one-dimensional chains well separated from each other by the Ph4P+ cations. Magnetic measurements show V to be a S = 1/2 and VI a S = O molecules. The distribution of electrons in these compounds have been determined by density functional theory calculations which show V to be a radical anion Ni(II) complex and VI a partially oxidized-ligand, reduced-copper complex. The 4,5 dithio-o-quinone [(Dtoq)2Ni][Ph4P]2 and [(Dtoq)2Cu][Ph4P]2 orthoquinone derivatives of V and VI have been obtained by oxidation, and their molecular structures have been determined. The dimeric {[FeS2C6H2(OH)2]2}2− complex, (VII) also crystallizes in chains where all OH groups participate in extensive H-bonding. The structure of the dianion VII contains S-coordinated Fe(III) ions in a square pyramidal coordination. In VII, two low spin Fe(III) (S = 1/2) sites are weakly coupled antiferromagnetically with a μeff of 2.81BM at 270 K and 0.91 BM at 10 K.