Convenient Syntheses of Trivalent Uranium Halide Starting Materials without Uranium Metal
Convenient Syntheses of Trivalent Uranium Halide Starting Materials without Uranium Metal
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不含铀金属的三价卤化铀起始材料的便捷合成
DOI：
10.1021/acs.inorgchem.1c00598
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发表时间：
2021
影响因子：
4.6
通讯作者：
Daly, Scott R.
中科院分区：
文献类型：
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作者：
Fetrow, Taylor V.;Grabow, J. Peter;Leddy, Johna;Daly, Scott R.
低价铀配位化学仍然严重依赖于获得三价原料，但这些试剂通常是从越来越难获得的铀转炉中制备的。在这里，我们报道了由UCl4方便地合成UI3(THF)4(THF=四氢呋喃)和UBr3(THF)4的方法。UCl4是一种更容易获得的铀原料，可以从商业上获得的铀氧化物中制备。UCl3(THF)2(1)、UBr3(THF)4(2)和UI3(THF)4(3)是由UCl4用KH和KC8单锅还原得到的，并通过与相应的Me3SiX(其中X=Br或I)进行卤化物交换而转化为2或3。UI4(Et2O)2(4；Et2O=二乙醚)和UI4(1，4-二氧六环)2(5)的还原也显示清洁地生成3。在U(BH4)4热还原得到的U(BH4)3(THF)2中加入无水HCl分别合成了配合物1。三种三价卤化铀配合物的结晶率均较高(通常为85-99%)，其组成经单晶X-射线衍射、元素分析、核磁共振氢谱和红外光谱确证。对暴露在真空中不同时间间隔的1-3个三联样品进行的元素分析表明，所有三个络合物在短短15分钟内都有显著的四氢呋喃损失。总体而言，这些结果为无法接触铀转化的研究人员提供了进入低价铀化学的便利条件。
Low-valent uranium coordination chemistry continues to rely heavily on access to trivalent starting materials, but these reagents are typically prepared from uranium turnings, which are becoming increasingly difficult to acquire. Here we report convenient syntheses of UI3(THF)4(THF = tetrahydrofuran) and UBr3(THF)4from UCl4, a more accessible uranium starting material that can be prepared from commercially available uranium oxides. UCl3(THF)2(1), UBr3(THF)4(2), and UI3(THF)4(3) were prepared by single-pot reductions from UCl4using KH and KC8and converted to2or3by halide exchange with the corresponding Me3SiX (where X = Br or I). Reduction of UI4(Et2O)2(4; Et2O = diethyl ether) and UI4(1,4-dioxane)2(5) was also shown to cleanly yield3. Complex1was also synthesized separately by the addition of anhydrous HCl to U(BH4)3(THF)2, which was prepared by thermal reduction of U(BH4)4. All three trivalent uranium halide complexes were isolated in high crystalline yields (typically 85–99%) and their formulations were confirmed by single-crystal X-ray diffraction, elemental analysis, and1H NMR and IR spectroscopy. Elemental analysis conducted on triplicate samples of1–3exposed to vacuum for different time intervals revealed significant THF loss for all three complexes in as little as 15 min. Overall, these results offer expedient entry into low-valent uranium chemistry for researchers lacking access to uranium turnings.