mild visible light-induced palladium-catalyzed alkyl Heckreaction of diazo compounds and N-tosylhydrazones is reported. This method features Brønsted acid assisted generation of hybrid palladium C(sp3)-centered radical intermediate and broad reaction scope, highlighting the diverse applicability and the potential utility of this protocol in late-stage functionalization.
A Neutral Metal-Free System for Head-to-Tail Dimerization of Electron-Rich Alkenes
作者:A-Yun Luo、Yan Bao、Xiu-Fen Cheng、Xi-Sheng Wang
DOI:10.1055/s-0036-1589039
日期:2017.9
Abstract A neutral metal-free system for the head-to-tail dimerization of electron-rich alkenes with stoichiometric amount of BrCCl2H and NaI is reported. This reaction proceeds under mild conditions with high efficiency and broad scope. A neutral metal-free system for the head-to-tail dimerization of electron-rich alkenes with stoichiometric amount of BrCCl2H and NaI is reported. This reaction proceeds
Mild and Regioselective Three‐component Heteroarylation‐Nitration of Alkenes with Imidazo[1,2‐
<i>a</i>
]pyridines and
<i>tert</i>
‐Butyl Nitrite
作者:Jie Zhang、Shentong Xie、Ping Liu、Peipei Sun
DOI:10.1002/adsc.202000078
日期:2020.5.26
An efficient and regioselective three‐component heteroarylation‐nitration of alkenes with imidazo[1,2‐a ]pyridines and tert ‐butyl nitrite has been developed. The process tolerants a variety of functional groups under mild conditions in the absence of catalysts and additives to give nitro functionalized imidazo[1,2‐a ]pyridine derivatives in moderate to good yields. The reaction is also applicable
已经开发了一种高效的区域选择性烯烃三元杂芳基硝化硝化反应,该硝化反应包括咪唑并[1,2- a ]吡啶和亚硝酸叔丁酯。在没有催化剂和添加剂的条件下,该工艺可在温和条件下耐受各种官能团,从而以中等至良好的收率得到硝基官能化的咪唑并[1,2- a ]吡啶衍生物。该反应也适用于其他一些氮杂杂环。
Radical Trifluoroacetylation of Alkenes Triggered by a Visible‐Light‐Promoted C–O Bond Fragmentation of Trifluoroacetic Anhydride
methodologies and occurs through a trifluoroacyl radical mechanism promoted by a photocatalyst, which triggers a C−O bond fragmentation. Mechanistic studies (kineticisotopeeffects, spectroelectrochemistry, optical spectroscopy, theoretical investigations) highlight the evidence of a fleeting CF3CO radical under photoredox conditions. The trifluoroacyl radical can be stabilized under CO atmosphere, delivering
我们报告了一种温和且操作简单的烯烃三氟酰化策略,该策略利用三氟乙酸酐作为低成本且易于获得的试剂。这种光介导的过程与传统方法有着根本的不同,它通过由光催化剂促进的三氟酰基自由基机制发生,从而触发 CO 键断裂。机理研究(动力学同位素效应、光谱电化学、光谱学、理论研究)突出了转瞬即逝的 CF 3的证据光氧化还原条件下的 CO 自由基。三氟酰基自由基可以在 CO 气氛下稳定,提供具有更高化学效率的三氟乙酰化产物。此外,该方法可以通过简单地改变反应参数变成三氟甲基化协议。除了简单的烯烃外,该方法还允许小分子药物和常见药效团的化学和区域选择性功能化。
Three-Component Visible-Light-Induced Palladium-Catalyzed 1,2-Alkyl Carbamoylation/Cyanation of Alkenes
作者:Xiangqing Jia、Ziyan Zhang、Vladimir Gevorgyan
DOI:10.1021/acscatal.1c04183
日期:2021.11.5
three-component alkyl-carbamoylation and cyanation of alkenes was developed. This general transformation, which proceeds via the in situ formation of a reactive ketenimine intermediate, allows for a rapid construction of a broad range of valuable amides and nitriles from readily available alkenes, alkyl iodides, and isocyanides. An efficient synthesis of tetrazole and amidine via this approach was also