高价锰(IV或V)-氧化卟啉被认为是锰卟啉催化剂在有机底物氧化中的反应性中间体。我们在碱性水溶液中生成了Mn V –和Mn IV –氧卟啉,并研究了它们在烃的CH键活化中的反应性。我们现在报告的Mn V -和Mn IV氧代卟啉能够活化的C 烷基芳烃的H键,用锰的反应性顺序V氧代>的Mn IV -氧代; 一Mn的反应性V -氧复合物比的锰更大150倍IV -氧复合物,呫吨的氧化。C基于反应速率与CH键离解能之间良好的线性相关性的观察结果,Mn V-和Mn IV-氧卟啉通过烷基芳烃的H键活化被认为是通过氢原子提取发生的。BDE)和and吨和二氢蒽(DHA)的氧化过程中的高动力学同位素效应(KIE)值。我们已经证明,Mn的歧化IV氧代卟啉与Mn V -氧和Mn III卟啉是不是在碱性水溶液中和的Mn可行途径IV氧代卟啉能够从烷基芳烃抽象的氢原子。的C 的Mn烷基芳烃的H键活化V -和Mn
Investigation of the Thermal and Photochemical Reactions of Ozone with 2,3-Dimethyl-2-butene
作者:Bridgett E. Coleman、Bruce S. Ault
DOI:10.1021/jp108457w
日期:2010.12.9
The matrixisolation technique, combined with infrared spectroscopy and twin jet codeposition, has been used to characterize intermediates formed during the ozonolysis of 2,3-dimethyl-2-butene (DMB). Absorptions of early intermediates in the twin jet experiments grew up to 200% upon annealing to 35 K. A number of these absorptions have been assigned to the elusive Criegee intermediate (CI) and secondary
Although CO does not dissociate on the clean Ir(111) surface, the addition of atomic oxygen induces COdissociation at low temperatures (lower than 400 K); similarly, COdissociation has also been observed on water co-adsorbed Ir(111) or water and oxygen co-adsorbed Ir(111).
spectroscopies, was used for characterization of the highly selective supported manganese–bismuth oxidecatalysts and for the study of the mechanism of the ammonia oxidation. Ammonia oxidation was demonstrated to proceed via alternating reduction and reoxidation of the catalyst surface with participation of the lattice oxygen. NH3 interacts with weakly bonded oxygen species through hydrogen atom abstraction to
A Thioether-Ligated Cupric Superoxide Model with Hydrogen Atom Abstraction Reactivity
作者:Mayukh Bhadra、Wesley J. Transue、Hyeongtaek Lim、Ryan E. Cowley、Jung Yoon C. Lee、Maxime A. Siegler、Patrick Josephs、Gerald Henkel、Markus Lerch、Siegfried Schindler、Adam Neuba、Keith O. Hodgson、Britt Hedman、Edward I. Solomon、Kenneth D. Karlin
DOI:10.1021/jacs.1c00260
日期:2021.3.17
([1]+), and its O2-bound analog [(TMGN3S)CuII(O2•–)]+ ([1·O2]+). The latter is the first reported cupric superoxide with an experimentally proven Cu–S bond which also possesses demonstrated hydrogenatomabstraction (HAA) reactivity. Introduction of O2 to a precooled solution of the cuprous precursor [1]B(C6F5)4 (−135 °C, 2-methyltetrahydrofuran (2-MeTHF)) reversibly forms [1·O2]B(C6F5)4 (UV/vis spectroscopy:
通过非偶联双核铜单加氧酶(如多巴胺-β-单加氧酶)在激素和神经递质生物合成中提出的超氧化铜中间体的核心作用引起了人们对此类铜M(“Cu B ”)活性位点的不寻常蛋氨酸连接的极大关注。酶。铜-硫的相互作用已被证明对营业额至关重要,这引发了关于 Nature 选择可氧化的 Met 残基以促进 C-H 氧化的仍未解决的问题。我们在此描述了 Cu M、[( TMG N 3 S)Cu I ] + ([ 1 ] + ) 及其 O 2的模型结合类似物[( TMG N 3 S)Cu II (O 2 •– )] + ([ 1 ·O 2 ] + )。后者是第一个报道的具有实验证明的 Cu-S 键的超氧化铜,该键还具有证明的氢原子夺取 (HAA) 反应性。将 O 2引入亚铜前体 [ 1 ]B(C 6 F 5 ) 4 (-135 °C, 2-甲基四氢呋喃 (2-MeTHF))的预冷溶液中可逆地形成 [ 1 ·O 2
Heme/Non-Heme Diiron(II) Complexes and O<sub>2</sub>, CO, and NO Adducts as Reduced and Substrate-Bound Models for the Active Site of Bacterial Nitric Oxide Reductase
作者:Ian M. Wasser、Hong-wei Huang、Pierre Moënne-Loccoz、Kenneth D. Karlin
DOI:10.1021/ja0458773
日期:2005.3.1
As a first generation model for the reactive reduced active-site form of bacterial nitric oxide reductase, a heme/non-hemediiron(II) complex [(6L)Fe(II)...Fe(II)-(Cl)]+ (2) where 6L = partially fluorinated tetraphenylporphyrin with a tethered tetradentate TMPA chelate; TMPA = tris(2-pyridyl)amine} was generated by reduction of the corresponding mu-oxo diferric compound [(6L)Fe(III)-O-Fe(III)-Cl]+
作为细菌一氧化氮还原酶的反应性还原活性位点形式的第一代模型,血红素/非血红素二铁 (II) 复合物 [(6L)Fe(II)...Fe(II)-(Cl)] + (2) 其中 6L = 部分氟化的四苯基卟啉与束缚的四齿 TMPA 螯合物;TMPA = 三(2-吡啶基)胺}是通过还原相应的 mu-氧代二铁化合物 [(6L)Fe(III)-O-Fe(III)-Cl]+ (1) 生成的。还开发了还原 NOR 与 O2、CO 和 NO 反应的配位化学模型。与 O2 和 CO 形成加合物,[(6L)Fe(III)(O2-))(thf)...Fe(II)-Cl]B(C6F5)4 (2a x O2) lambda(max) 418(索雷特),536 纳米;nu(OO) = 1176 cm(-1), nu(Fe-O) = 574 cm(-1) 和 [(6L)Fe(II)(CO)(thf)Fe(II)-Cl]B(C6F5)