Elucidating the Roles of Distinct Chemical Factors in the Hydrolytic Activities of Hetero- and Homonuclear Synthetic Analogues of Binuclear Metalloenzymes
Elucidating the Roles of Distinct Chemical Factors in the Hydrolytic Activities of Hetero- and Homonuclear Synthetic Analogues of Binuclear Metalloenzymes
复制标题
DOI：
10.1021/acscatal.2c05758
复制
发表时间：
2023-02
期刊：
影响因子：
12.9
通讯作者：
Vindi M. Jayasinghe-Arachchige;Leonardo F. Serafim;Qiaoyu Hu;C. Ozen;Sreerag N. Moorkkannur;G. Schenk;Rajeev Prabhakar
中科院分区：
文献类型：
--
作者：
Vindi M. Jayasinghe-Arachchige;Leonardo F. Serafim;Qiaoyu Hu;C. Ozen;Sreerag N. Moorkkannur;G. Schenk;Rajeev Prabhakar
在本研究中，采用DFT计算方法研究了非对称(I)或对称（II）配体与非对称(I)或对称（II）配体的异核和同核金属变体（分别为：IFZ、IZZ、iccoriifz、IIZZ和diicc）的水解活性，通过四种不同的机制：解离（DA）、底物辅助（SA）、水辅助（WA）和结合（AS）。此外，还计算了不同的亲核试剂（μ-OH、端- oh和-O2H3）、配位数、连接体的副取代基（-CH3、-Cl和-NO2）以及外加电场对这些反应能量学的影响。不对称(I)和对称（II）配体的三种金属中心的几何形状、自旋基态和底物结合模式彼此不同。二（2,4-二硝基苯）磷酸（BDNPP）底物没有路易斯酸活化，水解主要受金属结合羟基离子的亲核性控制。金属离子的电子性质决定了它们配合物的活性，而同核配合物是最活跃的配合物。然而，配体二形成的配合物对所有金属离子的活性并不比含配体二的配合物强。DFT计算表明，在四种途径中，DA途径在能量上是最可行的。末端羟基是最强的亲核试剂，给电子的- ch3基团是连接体中最合适的副取代基。而沿反应轴引入的外电场降低了ifz的势垒，使其保持不变而增加了icc的势垒。本研究的这些综合结果突出了不同的关键化学因素，如金属离子的电子性质，配体环境，以及连接剂和亲核试剂对磷酸酯水解的影响。所获得的见解将指导下一代多功能金属配合物的设计，用于广泛的反应和应用。
In this study, hydrolytic activities of hetero- and homobinuclear metallovariants of an asymmetric (I) or symmetric (II) ligand with the FeIII-ZnII, ZnII-ZnII, and CuII-CuIIcores (i.e.,IFZ,IZZ, andICCorIIFZ,IIZZ, andIICC, respectively) are investigated using DFT calculations through four distinct mechanisms: dissociative (DA), substrate-assisted (SA), water-assisted (WA), and associative (AS). Additionally, the effects of different nucleophiles (μ-OH, terminal-OH, and -O2H3), coordination numbers,parasubstituents (-CH3, -Cl, and -NO2) of the linker, and an external electric field on the energetics of these reactions are computed. The geometries, spin ground states, and substrate binding modes of the three metal centers for both asymmetric (I) and symmetric (II) ligands differ from each other. There is no Lewis acid activation of the bis(2,4-dinitrophenyl) phosphate (BDNPP) substrate, and hydrolysis is predominantly controlled by the nucleophilicity of the metal-bound hydroxyl ion. The electronic nature of the metal ions determines the activities of their complexes, and the homobinuclearIZZis found to be the most active complex. However, complexes formed with ligandIare not more active than their ligand-II-containing counterparts for all metal ions. The DFT calculations suggest that the DA pathway is the energetically most feasible among the four pathways. The terminal hydroxyl group is the strongest nucleophile, and the electron-donating -CH3group is the most suitableparasubstituent in the linker. Whereas the introduction of an external electric field along the reaction axis lowers the barrier forIFZ, it leaves that unchanged forIZZand increases that forICC. These combined results in this study highlight the influence of distinct critical chemical factors such as the electronic nature of the metal ions, the ligand environment, as well as the linker and nucleophile on phosphoester hydrolysis. Insights gained will guide the design of the next generation of versatile metal complexes for a wide range of reactions and applications.