Synthesis and Characterization of Two “Tied-Back” Lithium Ketimides and Isolation of a Ketimide-Bridged [Cr 2 ] 6+ Dimer with Strong Antiferromagnetic Coupling
Synthesis and Characterization of Two “Tied-Back” Lithium Ketimides and Isolation of a Ketimide-Bridged [Cr 2 ] 6+ Dimer with Strong Antiferromagnetic Coupling
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两种“绑回”酮亚胺锂的合成和表征以及具有强反铁磁耦合的酮亚胺桥联 [Cr 2 ] 6 二聚体的分离
DOI：
10.1021/acs.inorgchem.1c00052
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发表时间：
2021
影响因子：
4.6
通讯作者：
Hayton, Trevor W.
中科院分区：
文献类型：
--
作者：
Kent, Greggory T.;Cook, Andrew W.;Damon, Peter L.;Lewis, Richard A.;Wu, Guang;Hayton, Trevor W.
1 当量的 KN(SiMe3)2 与 9-芴酮反应，后处理后以高产率形成 (Me3Si)N=C13H8(1)。向 1 中添加 1 当量的苯酚会导致快速脱甲硅烷基化并形成 9-芴酮亚胺，HN=C13H8(2)。随后 2 与 1 当量的 LiNiPr2 反应导致去质子化并以良好的产率形成 [Li(Et2O)]4[N=C13H8]4(3)。 1当量的KN(SiMe3)2与2-金刚烷酮在室温下反应7天，以良好的收率形成(Me3Si)N=C10H14(4)。 4 在纯 MeOH 中的溶解导致快速脱甲硅烷基化，同时形成 2-金刚烷酮亚胺，HN=C10H14(5)。随后 5 与 1 当量的 LiNiPr2 反应生成 [Li(THF)]4[N=C10H14]4(6)。 3和6均通过X射线晶体学进行了表征。最后，CrCl3 与 3.5 当量的 6 反应形成 [Cr2]6+ 二聚体，[Li][Cr2(N=C10H14)7] (7)，后处理后可以以适度的产率分离。 Complex7 的 Cr-Cr 键长为 2.653(2) Å。此外，固态磁化率测量揭示了两个 Cr 中心之间的强反铁磁耦合，其中 J= -200 cm–1。
Reaction of 1 equiv of KN(SiMe3)2with 9-fluorenone results in the formation of (Me3Si)N═C13H8(1) in high yield after work-up. Addition of 1 equiv of phenol to1results in rapid desilylation and formation of 9-fluorenone imine, HN═C13H8(2). Subsequent reaction of2with 1 equiv of LiNiPr2results in deprotonation and formation of [Li(Et2O)]4[N═C13H8]4(3) in good yield. Reaction of 1 equiv of KN(SiMe3)2with 2-adamantanone for 7 days at room temperature results in the formation of (Me3Si)N═C10H14(4) in good yield. Dissolution of4in neat MeOH results in rapid desilylation concomitant with formation of 2-adamantanone imine, HN═C10H14(5). Subsequent reaction of5with 1 equiv of LiNiPr2results in formation of [Li(THF)]4[N═C10H14]4(6). Both3and6were characterized by X-ray crystallography. Finally, reaction of CrCl3with 3.5 equiv of6results in formation of the [Cr2]6+dimer, [Li][Cr2(N═C10H14)7] (7), which can be isolated in modest yield after work-up. Complex7features a Cr–Cr bond length of 2.653(2) Å. Additionally, solid-state magnetic susceptibility measurements reveal strong antiferromagnetic coupling between the two Cr centers, withJ= −200 cm–1.