Hydrodehalogenation of Aryl Halides through Direct Electrolysis
作者:Jie Ke、Hongling Wang、Liejin Zhou、Chengli Mou、Jingjie Zhang、Lutai Pan、Yonggui Robin Chi
DOI:10.1002/chem.201901082
日期:2019.5.17
hydrodehalogenation of aryl halides is disclosed. Our reaction by a flexible protocol is operated in an undivided cell equipped with an inexpensive graphite rod anode and cathode. Trialkylamines nBu3N/Et3N behave as effective reductants and hydrogen atom donors for this electrochemical reductive reaction. Various aryl and heteroaryl bromides worked effectively. The typically less reactive aryl chlorides
公开了无催化剂和无金属的芳基卤化物的电化学加氢脱卤。我们通过灵活的协议进行的反应在配备了廉价石墨棒阳极和阴极的不分隔电池中进行。三烷基胺n Bu 3 N / Et 3 N充当该电化学还原反应的有效还原剂和氢原子供体。各种芳基和杂芳基溴有效地起作用。通常反应性较低的芳基氯化物和氟化物也可以顺利转化。克农药规模的有害农药排毒和二溴代联苯的加氢溴化(阻燃剂类似物)证明了我们方法的实用性。
Cooperative Al–H Bond Activation in DIBAL-H: Catalytic Generation of an Alumenium-Ion-Like Lewis Acid for Hydrodefluorinative Friedel–Crafts Alkylation
作者:Francis Forster、Toni T. Metsänen、Elisabeth Irran、Peter Hrobárik、Martin Oestreich
DOI:10.1021/jacs.7b09444
日期:2017.11.15
donor-acceptor σ(Ru-H) → Al interaction. Despite the extra stabilization of the aluminum center by the interaction with both the sulfur atom and the Ru-H bond, the hydroalane adducts are found to be stronger Lewisacids and electrophiles than the free ruthenium catalyst and DIBAL-H in its different aggregation states. Hence, the DIBAL-H molecule and its Al-H bond are activated by the Ru-S bond, but these
Spectroscopic Capture and Reactivity of a Low-Spin Cobalt(IV)-Oxo Complex Stabilized by Binding Redox-Inactive Metal Ions
作者:Seungwoo Hong、Florian F. Pfaff、Eunji Kwon、Yong Wang、Mi-Sook Seo、Eckhard Bill、Kallol Ray、Wonwoo Nam
DOI:10.1002/anie.201405874
日期:2014.9.22
High‐valent cobalt‐oxo intermediates are proposed as reactiveintermediates in a number of cobalt‐complex‐mediated oxidation reactions. Herein we report the spectroscopic capture of low‐spin (S=1/2) CoIV‐oxo species in the presence of redox‐inactive metalions, such as Sc3+, Ce3+, Y3+, and Zn2+, and the investigation of their reactivity in CH bond activation and sulfoxidation reactions. Theoretical
高价钴氧中间体被认为是许多钴配合物介导的氧化反应中的反应中间体。在此,我们报告了在氧化还原惰性金属离子(例如 Sc 3+、Ce 3+、Y 3+和 Zn 2+ )存在下对低自旋 ( S =1/2) Co IV ‐oxo 物质的光谱捕获,并研究了它们在C - H键活化和磺化氧化反应中的反应活性。理论计算预测,路易斯酸性金属离子与钴氧核的结合增加了氧原子的亲电性,导致高度不稳定的 [(TAML)Co III (O . )] 2−物质发生氧化还原互变异构,形成更稳定的[(TAML)Co IV (O)(M n + )]核心。本报告支持氧化还原惰性金属离子在促进高价金属氧核的形成中的作用,这是化学和生物学中析氧的必要步骤。
Reductive transformations. 5. Alternative routes for reductive alkylations in liquid ammonia and their selection via spectroscopic evidence
Un grand nombre d'hydrocarbures insatures ont ete reduits par les metaux alcalins dans NH 3 liquide et les intermediaires carbanioniques ont ete detectes in situ par RMN et RPE. Les substrats sont partages en 3 groupes differents: a) ceux qui persistent comme dianions; b) ceux qui sont protones par NH 3 pour donner des anions monohydro; c) ceux qui subissent d'autres etapes de protonation/transfert
Un Grand nombre d'hydrocarbures insatures ont ete reduits par les metaux alcalins dans NH 3liquide et les intermediaires carbanioniques ont ete 在原位检测到 RMN 和 RPE。Les substrats sont partages en 3 groupes differents: a) ceux qui persistent comme dianions; b) ceux qui sont protones par NH 3 pour donner des anions monohydro;c) ceux qui subissent d'autres etapes de protonation/transfert d'electrons pour
A cobalt(<scp>ii</scp>) iminoiodane complex and its scandium adduct: mechanistic promiscuity in hydrogen atom abstraction reactions
remained elusive. Herein, we provide UV-Vis, EPR, NMR, XAS and DFT evidence supporting the formation of a metal–iminoiodane complex 2 and its scandium adduct 2-Sc. 2 and 2-Sc are reactive toward substrates in the hydrogen-atom and nitrene transfer reactions, which confirm their potential as active oxidants in metal-catalyzed oxidative transformations. Oxidation of para-substituted 2,6-di-tert-butylphenols
除了含氧金属[M n + O]和亚氨基金属[M n + NR]单元之外,过渡金属–碘亚芳烃[M (n -2)+ –O IPh]和金属–亚氨基碘[M (n −2)+ –N (R)IPh]加合物通常被称为可能的“第二氧化剂”,负责羰基和酰亚胺基团的转移反应。尽管最近已经分离和/或通过光谱表征了一些金属-碘杂芳烃加合物,但金属-亚氨基碘烷加合物仍然难以捉摸。在此,我们提供UV-Vis,EPR,NMR,XAS和DFT证据支持金属-亚氨基碘络合物2及其and加合物2-Sc的形成。2个2-Sc和2-Sc在氢原子和腈转移反应中对底物具有反应性,这证实了它们在金属催化的氧化转化中作为活性氧化剂的潜力。氧化对-取代的2,6-二-叔-butylphenols由2和2-Sc合金可由两个耦合和非耦合质子和电子转移机制发生; 确切的机制依赖于的性质对取代。