Elucidating Solution-State Coordination Modes of Multidentate Neutral Amine Ligands with Group-1 Metal Cations: Variable-Temperature NMR Studies.
Elucidating Solution-State Coordination Modes of Multidentate Neutral Amine Ligands with Group-1 Metal Cations: Variable-Temperature NMR Studies.
复制标题
DOI：
10.1021/acs.inorgchem.2c02457
复制
发表时间：
2022-09-26
影响因子：
4.6
通讯作者：
Lu, Erli
中科院分区：
文献类型：
--
作者：
Davison, Nathan;Quirk, James A.;Wills, Corinne;Dixon, Casey;Waddell, Paul G.;Dawson, James A.;Lu, Erli
多齿中性胺配体在配位化学和催化中起着重要的作用。特别是，这些配体被用来调节第一族金属试剂的反应性，例如有机锂试剂。这些第1族金属试剂介导的反应中，大多数(如果不是全部)都发生在溶液中。然而，与大量基于单晶X射线衍射的固体结构研究相比，这些配体与第一族金属阳离子的溶液-状态配位行为知之甚少。在这项工作中，我们全面地绘制了三个多齿中性胺配体1，4，7-三甲基-1，4，7-三氮杂环酮(Me3TACN)、四齿三[2-(二甲氨基)乙基]胺(Me6Tren)和六齿N，N‘，N″-tris-(2-N-diethylaminoethyl)-1，4，7-triaza-cyclononane(DETAN)与1族金属阳离子的配位模式。Me3TACN和DETAN中的大环被确定为刚性结构导向基序，DETAN的侧臂提供了灵活的“按需”协调位置。相比之下，Me6Tren配体的配位更强健，侧臂不太可能经历去配位-配位平衡。这项工作将为配位化学家应用这三种配体，特别是新的DETAN配体来设计符合其目的的金属配合物提供指导。结合变温核磁共振(VT NMR)和密度泛函理论(DFT)计算，研究了三种中性多齿胺配体与1族金属离子的溶液配位模式。我们的研究证明，两个配体设计的构件，即N-大环(TACN)和N-侧臂，分别作为结构决定和半分子配位。这一概念可以用于设计新的催化系统，该系统将金属中心固定在大循环上，而侧武器则充当“按需”保护性的协调位置。
Multidentate neutral amine ligands play vital roles in coordination chemistry and catalysis. In particular, these ligands are used to tune the reactivity of Group-1 metal reagents, such as organolithium reagents. Most, if not all, of these Group-1 metal reagent-mediated reactions occur in solution. However, the solution-state coordination behaviors of these ligands with Group-1 metal cations are poorly understood, compared to the plethora of solid-state structural studies based on single-crystal X-ray diffraction (SCXRD) studies. In this work, we comprehensively mapped out the coordination modes with Group-1 metal cations for three multidentate neutral amine ligands: tridentate 1,4,7-trimethyl-1,4,7-triazacyclononane (Me3TACN), tetradentate tris[2-(dimethylamino)ethyl]amine (Me6Tren), and hexadentate N,N′,N″-tris-(2-N-diethylaminoethyl)-1,4,7-triaza-cyclononane (DETAN). The macrocycles in the Me3TACN and DETAN are identified as the rigid structural directing motif, with the sidearms of DETAN providing flexible “on-demand” coordination sites. In comparison, the Me6Tren ligand features more robust coordination, with the sidearms less likely to undergo the decoordinating–coordinating equilibrium. This work will provide a guidance for coordination chemists in applying these three ligands, in particular, the new DETAN ligand to design metal complexes which suit their purposes. Combining variable-temperature nuclear magnetic resonance (VT NMR) and DFT calculations, this work elucidates the solution-state coordination modes of three multidentate neutral amine ligands with Group-1 metal cations. Our studies prove that two ligand-design building blocks, that is, N-macrocycle (TACN) and N-sidearms, act as structure-dictating and hemilabile coordinating sites, respectively. The concept could be utilized in designing new catalytic systems, which anchor the metal center on the macrocycle, while the sidearms serve as “on-demand” protective coordination sites.
登录
查看更多内容
DOI：
10.1021/acs.joc.0c02546
发表时间：
2021-02-05
期刊：
The Journal of organic chemistry
影响因子：
--
作者：
Woltornist RA;Collum DB
通讯作者：
Collum DB
具有1组金属阳离子的多齿中性胺配体的多齿中性胺配体的多功能配位模式。
影响因子：
4.6
作者：
Davison, Nathan;Zhou, Ke;Waddell, Paul G.;Wills, Corinne;Dixon, Casey;Hu, Shu-Xian;Lu, Erli
通讯作者：
Lu, Erli
影响因子：
16.6
作者：
Poeppler, Ann-Christin;Granitzka, Markus;Stalke, Dietmar
通讯作者：
Stalke, Dietmar
影响因子：
4.9
作者：
Bachmann, Sebastian;Gernert, Bjoern;Stalke, Dietmar
通讯作者：
Stalke, Dietmar
影响因子：
4.9
作者：
Davison, Nathan;Falbo, Emanuele;Lu, Erli
通讯作者：
Lu, Erli