Kiernicki John J, Tatebe Caleb J, Zeller Matthias, Bart Suzanne C
H.C. Brown Laboratory, Department of Chemistry, Purdue University , West Lafayette, Indiana 47907, United States.
Inorg Chem. 2018 Feb 19;57(4):1870-1879. doi: 10.1021/acs.inorgchem.7b02791. Epub 2018 Feb 8.
Uranium mono(imido) species have been prepared via the oxidation of CpU(PDI)(THF) (1-Cp) and [CpU(PDI)] (1-Cp), where Cp* = η-1,2,3,4,5-pentamethylcyclopentadienide, Cp = 1-(7,7-dimethylbenzyl)cyclopentadienide, PDI = 2,6-[(Mes)N═CMe]CHN, and Mes = 2,4,6-trimethylphenyl, with organoazides. Treating either with NDIPP (DIPP = 2,6-diisopropylphenyl) formed uranium(IV) mono(imido) complexes, CpU(NDIPP)(PDI) (2-Cp) and CpU(NDIPP)(PDI) (2-Cp), featuring reduced [PDI]. The addition of electron-donating 1-azidoadamantane (NAd) to 1-Cp* generated a dimeric product, [CpU(NAd)(HPDI)] (3), from radical coupling at the p-pyridine position of the pyridine(diimine) ligand and H-atom abstraction, formed through a monomeric intermediate that was observed in solution but could not be isolated. To support this, CpU(Bu-PDI)(THF) (1-Bu), which has a tert-butyl group protecting the para position, was also treated with NAd, and the monomeric product, Cp*U(NAd)(Bu-PDI) (2-Bu), was isolated. All isolated complexes were analyzed spectroscopically and structurally, and the dynamic solution behavior was examined using electronic absorption spectroscopy.
通过用有机叠氮化物氧化CpU(PDI)(THF) (1-Cp)和[CpU(PDI)] (1-Cp)制备了单(亚胺基)铀物种，其中Cp* = η-1,2,3,4,5-五甲基环戊二烯基，Cp = 1-(7,7-二甲基苄基)环戊二烯基，PDI = 2,6-[(Mes)N═CMe]CHN，Mes = 2,4,6-三甲基苯基。用NDIPP（DIPP = 2,6-二异丙基苯基）处理这两种物质均形成了铀(IV)单(亚胺基)配合物CpU(NDIPP)(PDI) (2-Cp)和CpU(NDIPP)(PDI) (2-Cp)，其特征在于[PDI]降低。向1-Cp中加入给电子的1-叠氮基金刚烷（NAd）生成了二聚产物[CpU(NAd)(HPDI)] (3)，它是通过吡啶（二亚胺）配体的对吡啶位置的自由基偶联和氢原子夺取形成的，通过在溶液中观察到但无法分离的单体中间体形成。为了支持这一点，还用NAd处理了具有叔丁基保护对位的CpU(Bu-PDI)(THF) (1-Bu)，并分离出了单体产物CpU(NAd)(Bu-PDI) (2-Bu)。对所有分离出的配合物进行了光谱和结构分析，并使用电子吸收光谱研究了动态溶液行为。
