Probing Ligand Effects on the Ultrafast Dynamics of Copper Complexes via Midinfrared Pump-Probe and 2DIR Spectroscopies.
Probing Ligand Effects on the Ultrafast Dynamics of Copper Complexes via Midinfrared Pump-Probe and 2DIR Spectroscopies.
复制标题
DOI：
10.1021/acs.jpcb.1c06370
复制
发表时间：
2021-11-11
影响因子：
3.3
通讯作者：
Anna, Jessica M.
中科院分区：
文献类型：
--
作者：
Weng, Wei;Weberg, Alexander B.;Gera, Rahul;Tomson, Neil C.;Anna, Jessica M.
使用偏振相关的中红外泵浦探针光谱和二维红外（2DIR）光谱研究了配体结构变化对一系列铜配位配合物超快动力学的影响。该系列由三种铜配合物 [(R3P3tren)CuIIN3]BArF4（1PR3 、R3P3tren = 三[2-（亚膦酰基）乙基]胺、BArF4 = 四（五氟苯基）硼酸盐）组成，其中 PR3 配体中甲基和苯基的数量在整个系列中系统地变化（PR3 = PMe3、PMe2Ph、PMePh2）。 1PR3系列中叠氮化物的不对称伸缩模式被用作小分子结合位点的振动探针。泵探针测量的结果表明，叠氮化物的振动能量通过分子内途径耗散，并且较大的苯基导致结合叠氮化物的扩散重新取向的空间限制增加。通过 2DIR 实验，我们描述了叠氮基团的光谱扩散，发现苯基数量的增加映射到更广泛的不均匀频率分布 (Δ2)。这表明二级配位球空间体积的增加可在局部环境中创建叠氮基团可访问的更独特的构型。这项工作展示了配体结构变化如何影响与金属中心结合的小分子基团的超快动力学，这可以深入了解铜配位络合物和过渡金属配位络合物的结构-功能关系。
The effects of ligand structural variation on the ultrafast dynamics of a series of copper coordination complexes were investigated using polarization-dependent mid-IR pump probe spectroscopy and two-dimensional infrared (2DIR) spectroscopy. The series consists of three copper complexes [(R3P3tren)CuIIN3]BArF4 (1PR3 ,R3P3tren = tris[2-(phosphiniminato)ethyl]amine, BArF4 = tetrakis(pentafluorophenyl)borate) where the number of methyl and phenyl groups in the PR3 ligand are systematically varied across the series (PR3 = PMe3, PMe2Ph, PMePh2). The asymmetric stretching mode of azide in the 1PR3 series is used as a vibrational probe of the small molecule binding site. The results of the pump probe measurements indicate that the vibrational energy of azide dissipates through intramolecular pathways and that the bulkier phenyl groups lead to an increase in the spatial restriction of the diffusive reorientation of bound azide. From 2DIR experiments we characterize the spectral diffusion of the azide group and find that an increase in the number of phenyl groups maps to a broader inhomogeneous frequency distribution (Δ2). This indicates that an increase in the steric bulk of the secondary coordination sphere acts to create more distinct configurations in the local environment that are accessible to the azide group. This work demonstrates how ligand structural variation affects the ultrafast dynamics of a small molecular group bound to the metal center, which could provide insight into the structure-function relationship of the copper coordination complexes, and transition metal coordination complexes in general.
登录
查看更多内容
影响因子：
3.3
作者：
Bagchi, Sayan;Boxer, Steven G.;Fayer, Michael D.
通讯作者：
Fayer, Michael D.
影响因子：
62.1
作者：
Elwell CE;Gagnon NL;Neisen BD;Dhar D;Spaeth AD;Yee GM;Tolman WB
通讯作者：
Tolman WB
影响因子：
2.9
作者：
Brookes, Jennifer F.;Slenkamp, Karla M.;Khalil, Munira
通讯作者：
Khalil, Munira
影响因子：
5.7
作者：
Gera, Rahul;Meloni, Stephen L.;Anna, Jessica M.
通讯作者：
Anna, Jessica M.
影响因子：
1.6
作者：
Hayashi, H;Uozumi, K;Kitagawa, T
通讯作者：
Kitagawa, T