Uranium(III) Coordination Chemistry and Oxidation in a Flexible Small-Cavity Macrocycle
Uranium(III) Coordination Chemistry and Oxidation in a Flexible Small-Cavity Macrocycle
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DOI：
10.1021/om5012193
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发表时间：
2015-06-08
期刊：
影响因子：
2.8
通讯作者：
Love, Jason B.
中科院分区：
文献类型：
--
作者：
Arnold, Polly L.;Farnaby, Joy H.;Love, Jason B.
由构象灵活的小腔大环反式杯[2]苯[2]吡咯（L）（2）形成的U(III)配合物，[U(L)X]（X = O - 2,6 - 叔丁基（2）C₆H₃，N(三甲基硅基)₂）已由[U(L)BH₄]合成并进行了结构表征。这些配合物显示U(III)中心结合在大环的双（芳烃）口袋中，大环发生弯曲以适应X空间位阻的增加，导致与辅助配体形成较长的UX键。氧化为阳离子U(IV)配合物[U(L)X][B(C₆F₅)₄]（X = BH₄）会导致配体重排，使较小、较硬的阳离子结合在双（吡咯）口袋中，其构象是（L）²⁻之前未观察到的，X位于两个配体芳烃环之间。
U(III) complexes of the conformationally flexible, small-cavity macrocycle trans-calix[2]benzene[2]pyrrolide (L)(2), [U(L)X] (X = O-2,6-tBu(2)C(6)H(3), N(SiMe3)(2)), have been synthesized from [U(L)BH4] and structurally characterized. These complexes show binding of the U(III) center in the bis(arene) pocket of the macrocycle, which flexes to accommodate the increase in the steric bulk of X, resulting in long UX bonds to the ancillary ligands. Oxidation to the cationic U(IV) complex [U(L)X][B(C6F5)(4)] (X = BH4) results in ligand rearrangement to bind the smaller, harder cation in the bis(pyrrolide) pocket, in a conformation that has not been previously observed for (L)(2-), with X located between the two ligand arene rings.