New route to the mixed valence semiquinone-catecholate based mononuclear   Fe-III and catecholate based dinuclear Mn-III complexes: First   experimental evidence of valence tautomerism in an iron complex

doi:10.1021/ic049579i

CORC > 北京大学 > 化学与分子工程学院

	New route to the mixed valence semiquinone-catecholate based mononuclear Fe-III and catecholate based dinuclear Mn-III complexes: First experimental evidence of valence tautomerism in an iron complex
	Shaikh, N ; Goswami, S ; Panja, A ; Wang, XY ; Gao, S ; Butcher, RJ ; Banerjee, P
刊名	inorganic chemistry
	2004
关键词	TRANSITION-METAL-COMPLEXES QUINONE COMPLEXES ELECTRON-TRANSFER CHARGE-DISTRIBUTION REDOX ISOMERISM LIGANDS SERIES MANGANESE INTERCONVERSION BENZOQUINONE
DOI	10.1021/ic049579i
英文摘要	The semiquinone-catecholate based mixed valence complex, [Fe-III(bispicen) (Cl(4)Cat) (Cl(4)SQ)].DMF (1), and catecholate based (H(2)bispictn)[Mn-2(III)(Cl(4)Cat)(4)(DMF)(2)] (2) (bispicen N,N'-bis(2-pyridylmethyl)-1,2-ethanediamine, bispictn = N,N'-bis(2-pyridylmethyl)-1,3-propanediamine, Cl(4)Cat = tetrachlorocatecholate dianion, and Cl(4)SQ = tetrachloroserniquinone radical anion) were synthesized directly utilizing a facile route. Both the complexes have been characterized by single crystal X-ray diffraction study. The electronic structures have been elucidated by UV-vis-NIR absorption spectroscopy, cyclic voltammetry, EPR, and magnetic properties. The structural as well as spectroscopic features support the mixed valence tetrachlorosemiquinone-tetrachlorocatecholate charge distribution in 1. The ligand based mixed valence state was further confirmed by the presence of an intervalence charge transfer (IVCT) band in the 1900 nm region both in solution and in the solid. The intramolecular electron transfer, a phenomenon known as valence tautomerism (VT), has been followed by electronic absorption spectroscopy. For 1, the isomeric form [Fe-III(bispicen)(Cl(4)Cat) (Cl(4)SQ) is favored at low temperature, while at an elevated temperature, the [Fe-III(bispicen)(Cl(4)SQ)(2)] redox isomer dominates. Infrared as well as UV-vis-NIR spectral characterization for 2 suggest that the Mn-III(Cat)(2)(-) moiety is admixed with its mixed valence serniquinone-catecholate isomer Mn-III(SQ)(Cat)(-), and the electronic absorption spectrum is dominated by the mixed charged species. The origin of the intervalence charge transfer band in the 1900 nm range is associated with the mixed valence form, Mn-III(Cl(4)Cat)(Cl(4)SQ)(-). The observation of VT in complex 1 is the first example where a mixed valence semiquinonecatecholate iron(III) complex undergoes intramolecular electron transfer similar to manganese and cobalt complexes.; Chemistry, Inorganic & Nuclear; SCI(E); 0; ARTICLE; 19; 5908-5918; 43
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/254072]
专题	化学与分子工程学院
推荐引用方式 GB/T 7714	Shaikh, N,Goswami, S,Panja, A,et al. New route to the mixed valence semiquinone-catecholate based mononuclear Fe-III and catecholate based dinuclear Mn-III complexes: First experimental evidence of valence tautomerism in an iron complex[J]. inorganic chemistry,2004.
APA	Shaikh, N.,Goswami, S.,Panja, A.,Wang, XY.,Gao, S.,...&Banerjee, P.(2004).New route to the mixed valence semiquinone-catecholate based mononuclear Fe-III and catecholate based dinuclear Mn-III complexes: First experimental evidence of valence tautomerism in an iron complex.inorganic chemistry.
MLA	Shaikh, N,et al."New route to the mixed valence semiquinone-catecholate based mononuclear Fe-III and catecholate based dinuclear Mn-III complexes: First experimental evidence of valence tautomerism in an iron complex".inorganic chemistry (2004).