Metal (III) Complex Of Biuret-Amide Based Macrocyclic Ligand As Green Oxidation Catalyst
申请人:Sengupta Sayam
公开号:US20120329680A1
公开(公告)日:2012-12-27
The present invention discloses metal (III) complex of a biuret-amide based macrocyclic ligand as green catalysts that exhibit both excellent reactivity for the activation of H
2
O
2
and high stability at low pH and high ionic strength. The invention also provides macrocyclic biuret amide based ligand for designing of functional peroxidase mimics. Further, the present invention discloses synthesis of said metal (III) complex of a biuret-amide based macrocyclic ligand.
Buffer anion effects on water oxidation catalysis: The case of Cu(III) complex
作者:Qifa Chen、Haoyi Du、Mingtian Zhang
DOI:10.1016/s1872-2067(20)63729-9
日期:2021.8
Water oxidation is the bottleneck of artificial photosynthesis. Since the first ruthenium-based molecular water oxidation catalyst, the blue dimer, was reported by Meyer's group in 1982, catalysts based on transitionmetals have been widely employed to explore the mechanism of water oxidation. Because the oxidation of water requires harsh oxidative conditions, the stability of transition complexes
Homogeneous Electrochemical Water Oxidation at Neutral pH by Water‐Soluble Ni
<sup>II</sup>
Complexes Bearing Redox Non‐innocent Tetraamido Macrocyclic Ligands
作者:Husileng Lee、Xiujuan Wu、Licheng Sun
DOI:10.1002/cssc.202000153
日期:2020.6.19
Wateroxidation is the bottleneck reaction in artificial photosynthesis. Exploring highly active and stable molecular wateroxidation catalysts (WOCs) is still a great challenge. In this study, a water‐soluble NiII complex bearing a redox non‐innocent tetraamido macrocyclic ligand (TAML) is found to be an efficient electrocatalyst for wateroxidation in neutral potassium phosphate buffer. Controlled‐potential
水的氧化是人工光合作用的瓶颈反应。探索高活性和稳定的分子水氧化催化剂(WOC)仍然是一个巨大的挑战。在这项研究中,发现带有氧化还原非纯四酰胺基大环配体(TAML)的水溶性Ni II络合物是中性磷酸钾缓冲液中水氧化的有效电催化剂。受控电位电解实验表明,与正常的氢电极(NHE)相比,它在1.75 V的稳定电流下,在约0.2 mA cm -2的恒定电流下可维持> 7 h的时间,而不会形成NiO x。电化学和光谱电化学测试表明,氧化还原活性配体以及HPO 4 2-在缓冲液中,参与催化循环。更重要的是,具有催化活性的中间体[Ni III(TAML 2-)-O 。]是通过几个质子耦合的电子转移过程形成的,并在碱的帮助下与H 2 O反应释放出分子氧。因此,采用氧化还原非纯配体是设计有效分子WOC的有用策略。
Preparation and Characterization of a Formally Ni<sup>IV</sup>–Oxo Complex with a Triplet Ground State and Application in Oxidation Reactions
作者:Deepika G. Karmalkar、Virginia A. Larson、Deesha D. Malik、Yong-Min Lee、Mi Sook Seo、Jin Kim、Dovydas Vasiliauskas、Jason Shearer、Nicolai Lehnert、Wonwoo Nam
DOI:10.1021/jacs.2c10196
日期:2022.12.14
XAS data indicate that the complex contains a Ni(III) center, which results from an unusually large degree of Ni–O π-bond inversion, with one hole located on the oxo ligand. The complex is therefore best described as a low-spin Ni(III) complex (S = 1/2) with a bound oxyl (O•–) ligand (S = 1/2), where the spins of Ni and oxyl are ferromagnetically coupled, giving rise to the observed St = 1 ground state
高价第一行过渡金属-氧代络合物是有机分子在生物学和化学上相关的氧化转化以及(人工)光合作用中的水分解反应中的重要中间体。虽然高价 Fe- 和 Mn-oxo 络合物已被详细表征,但对它们与后过渡金属的类似物知之甚少。在这项研究中,我们介绍了一种独特的单核末端 Ni-O 络合物的合成和详细表征。这种化合物 [Ni(TAML)(O)(OH)] 3–的特征在于 730 nm 附近的强电荷转移 (CT) 带,并且具有S t= 1 基态,由磁性圆二色光谱确定。根据扩展 X 射线吸收精细结构 (EXAFS),Ni-O 键距为 1.84 Å。Ni K 边缘 XAS 数据表明该络合物包含一个 Ni(III) 中心,这是由异常大程度的 Ni-O π 键反转产生的,其中一个孔位于氧代配体上。因此,该络合物最好被描述为低自旋 Ni(III) 络合物 ( S = 1/2) 与结合的氧基 (O •– ) 配体 ( S
A Chemical Model of a TET Enzyme for Selective Oxidation of Hydroxymethyl Cytosine to Formyl Cytosine
作者:Dipanwita Palit、Shubhankar Kundu、Pritam Kumar Pain、Rajdeep Sarma、Debasish Manna
DOI:10.1021/acs.inorgchem.3c00063
日期:2023.7.3
conditions. Detailed HPLC analyses supported by a wide reaction condition optimization for the 5-hmC → 5-fC oxidation provides us with a chemicalmodel of the TET enzyme. This study shines light on future efforts for a better understanding of the roles of 5-hmC and the TET enzyme mechanism and potentially novel therapeutic methods.
DNA 中胞嘧啶的甲基化/去甲基化是表观遗传学的核心,表观遗传学在大约一半的人类基因的调节中发挥着至关重要的作用。尽管下调基因表达的甲基化机制已被充分解码;上调基因表达的去甲基化途径仍然有待解答的问题。10-11 易位 (TET) 酶对 5-甲基胞嘧啶进行去甲基化,产生尚未研究但与表观遗传学相关的中间体:5-羟甲基 (5-hmC)、5-甲酰基 (5-fC) 和 5-羧基 (5-caC) 胞嘧啶。在这里,我们报道了一种铁配合物 Fe III TAML(TAML = 四酰胺大环配体),它可以通过在 H 2存在下形成高价 Fe-oxo 中间体来促进 5-hmC 选择性氧化为其氧化衍生物。O 2在生理相关条件下。由 5-hmC → 5-fC 氧化的广泛反应条件优化支持的详细 HPLC 分析为我们提供了 TET 酶的化学模型。这项研究揭示了未来为更好地了解 5-hmC 的作用和 TET 酶机制以及潜在的新颖治疗方法所做的努力。