Properties of Square-Pyramidal Alkyl−Thiolate Fe<sup>III</sup> Complexes, Including an Analogue of the Unmodified Form of Nitrile Hydratase
作者:Priscilla Lugo-Mas、Wendy Taylor、Dirk Schweitzer、Roslyn M. Theisen、Liang Xu、Jason Shearer、Rodney D. Swartz、Morgan C. Gleaves、Antonio DiPasquale、Werner Kaminsky、Julie A. Kovacs
DOI:10.1021/ic801704n
日期:2008.12.1
square-pyramidal thiolate-ligated Fe(III) complexes are described, [Fe(III)((tame-N(3))S(2)(Me2))](+) (1), [Fe(III)(Et-N(2)S(2)(Me2))(py)](1-) (3), and [Fe(III)((tame-N(2)S)S(2)(Me2))](2-) (15). The anionic bis-carboxamide, tris-thiolate N(2)S(3) coordination sphere of 15 is potentially similar to that of the yet-to-be characterized unmodified form of NHase. Comparison of the magnetic and reactivity properties
描述了三种新的配位不饱和,单体,方形-金字塔形的硫醇盐键合的Fe(III)配合物的合成和结构,[Fe(III)((tame-N(3))S(2)(Me2))]( +)(1),[Fe(III)(Et-N(2)S(2)(Me2))(py)](1-)(3)和[Fe(III)((tame-N( 2)S)S(2)(Me2))](2-)(15)。阴离子双羧酰胺,三硫醇盐N(2)S(3)配位域为15,可能与尚未表征的NHase形式相似。这些磁性和反应性的比较表明,阴离子电荷是如何建立的(从阳离子1到阴离子3和双阴离子15)和自旋态影响顶配体亲和力。对于所有检查的配体场组合,中间S = 3/2自旋态显示出较强的N(2)S(2)基础平面配体场,这被发现降低了对根尖的亲和力配体 即使它们是内置的,也与翻译后修饰的NHase活性位点相反,后者旋转性低,并且对顶端配体的亲和力更高。阳离子1及其还原的Fe(II)前体