SYNTHESIS AND PROPERTIES OF HIGH-VALENT ORGANOURANIUM COMPLEXES CONTAINING TERMINAL ORGANOIMIDO AND OXO FUNCTIONAL-GROUPS - A NEW CLASS OF ORGANO-F-ELEMENT COMPLEXES
SYNTHESIS AND PROPERTIES OF HIGH-VALENT ORGANOURANIUM COMPLEXES CONTAINING TERMINAL ORGANOIMIDO AND OXO FUNCTIONAL-GROUPS - A NEW CLASS OF ORGANO-F-ELEMENT COMPLEXES
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DOI：
10.1021/ja00142a011
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发表时间：
1995-09-20
影响因子：
15
通讯作者：
BURNS, CJ
中科院分区：
文献类型：
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作者：
ARNEY, DSJ;BURNS, CJ
采用复分解法和直接质子化法制备了铀（IV）的单亚胺衍生物。在四亚甲基乙二胺（TMED）存在下，苯胺锂与(eta(5)-C(5)Me(5))(2)UMeCl反应，分离出盐[Li(TMED)][eta(5)-C(5)Me(5))(2)U(NC6H5)Cl](1)。化合物1在空间群P3(2)中结晶，晶胞尺寸a = 17.545(2)埃，c = 9.407(2)埃，V = 2507.8(7)埃(3),Z = 3。与苯胺盐钾的复分解反应同样导致U（IV）的单亚胺氯阴离子衍生物的形成；这些可以在室温下与适当的路易斯碱反应转化为中性碱加合物。一个更直接的形成中性有机亚胺的途径是(eta(5)-C(5)Me(5))(2)UMe(2)与1等量H2NAr （Ar = 2,6-二异丙基苯基或2,4,6-三叔丁基苯基）的反应。无碱的2,6-二异丙基衍生物在所有溶剂中都是高度可溶的，该质子化反应的产物最好分离为碱加合物(eta(5)-C(5)Me(5))(2)U(n -2,6-i- pr2c6h3)（THF)(6)）。然而，2,4,6-三叔丁基苯基苯胺产物不与四氢呋喃进一步反应，并且可以分离为无碱的亚胺配合物(eta(5)-C-5-Me(5))(2)U(n -2,4,6-t- bu (3)C(6)H(2))(8)化合物8在Pmn2(1)空间群中结晶，单位胞尺寸为a = 13.450(5)埃，b = 12.138(5)埃，C = 10.510(3)埃，V = 1715.9（10）埃(3),Z = 2。所有的铀（IV）有机亚胺化合物都表现出丰富的化学性质，具有两种电子氧化原子转移试剂，提供了一类全新的含有末端亚胺和氧官能团的有机铀（VI）配合物。双（亚胺）配合物如(eta(5)-C(5)M(5))(2)U(NC6H5)(2)(3)也可以通过在铀（IV）中心对1,2-二苯基肼进行前所未有的分子内还原裂解制备。这些配合物通常不具有反应性，但化合物3会使二氢发生前所未有的均裂裂解，生成双（酰胺）衍生物。这些物质的物理性质和化学稳定性表明，它们具有显著的铀-亚胺和-氧多键特征。
Monoimido derivatives of uranium(IV) have been prepared by both metathesis and direct protonation routes. The reaction of lithium anilide with (eta(5)-C(5)Me(5))(2)UMeCl in the presence of tetramethylethylenediamine (TMED) results in the isolation of the salt [Li(TMED)][eta(5)-C(5)Me(5))(2)U(NC6H5)Cl] (1). Compound 1 crystallizes in the space group P3(2), with unit cell dimensions a = 17.545(2) Angstrom, c = 9.407(2) Angstrom, V = 2507.8(7) Angstrom(3), Z = 3. Metathesis reactions with potassium anilide salts similarly result in the formation of monoimido chloride anionic derivatives of U(IV); these can be converted to neutral base adducts by reaction with the appropriate Lewis base at room temperature. A more direct route to the formation of neutral organoimido species with sterically encumbered aryl substituents is the reaction of (eta(5)-C(5)Me(5))(2)UMe(2) with 1 equiv H2NAr (Ar = 2,6-diisopropylphenyl or 2,4,6-tri-tert-butylphenyl). The base-free 2,6-diisopropyl derivative is highly soluble in all solvents, and the product of this protonation is best isolated as a base adduct, (eta(5)-C(5)Me(5))(2)U(N-2,6-i-Pr2C6H3)(THF) (6). The 2,4,6-tri-tert-butylphenylaniline product does not react further with tetrahydrofuran, however, and may be isolated as the base-free imido complex (eta(5)-C-5-Me(5))(2)U(N-2,4,6-t-Bu(3)C(6)H(2)) (8) Compound 8 crystallizes in the space group Pmn2(1), with unit cell dimensions a = 13.450(5) Angstrom, b = 12.138(5) Angstrom, c = 10.510(3) Angstrom, V = 1715.9(10) Angstrom(3), Z = 2. All of the organoimido compounds of uranium(IV) exhibit rich chemistry with two electron oxidative atom transfer reagents, providing an entirely new class of organouranium(VI) complexes containing terminal imido and oxo functional groups. Bis(imido) complexes such as (eta(5)-C(5)M(5))(2)U(NC6H5)(2) (3) can also be prepared by the unprecedented intramolecular reductive cleavage of 1,2-diphenylhydrazine at a uranium(IV) center. These complexes are in general surprisingly unreactive, but compound 3 will effect the unprecedented homolytic cleavage of dihydrogen to yield a bis(amide) derivative. The physical properties and chemical stability of these species suggests that significant uranium-imido and -oxo multiple bond character is present.