Recyclable heterogeneous gold(I)-catalyzed oxidation of internal acylalkynes: Practical access to vicinal tricarbonyls
作者:Wenli Hu、Bin Huang、Bingbo Niu、Mingzhong Cai
DOI:10.1016/j.tetlet.2021.152953
日期:2021.3
A highly efficient heterogeneous gold(I)-catalyzed oxidation of internal acylalkynes has been developed using 2,6-dichloropyridine N-oxide as the oxidant in dichloromethane (CH2Cl2) at room temperature, providing a novel and practical approach for the construction of diverse vicinal tricarbonyls such as α,β-diketoesters, 1,2,3-triketones, and α,β-diketoamides in good to excellent yields. The heterogeneous
Room Temperature Metal-Catalyzed Oxidative Acylation of Electron-Deficient Heteroarenes with Alkynes, Its Mechanism, and Application Studies
作者:Shweta Sharma、Mukesh Kumar、Ram A. Vishwakarma、Mahendra K. Verma、Parvinder Pal Singh
DOI:10.1021/acs.joc.8b01475
日期:2018.10.19
room-temperature, regioselective Minisci reaction for the acylation of electron-deficient heteroarenes with alkynes. The method has broad functional group compatibility and gives exclusively monoacylated products in good to excellent yields. The mechanistic pathway was analyzed based on a series of experiments confirming the involvement of a radical pathway. The 18O-labeling experiment suggested that water
Acyl Radicals from Terminal Alkynes: Photoredox-Catalyzed Acylation of Heteroarenes
作者:Shaista Sultan、Masood Ahmad Rizvi、Jaswant Kumar、Bhahwal Ali Shah
DOI:10.1002/chem.201801628
日期:2018.7.25
A photoredox‐mediated acylation reaction of electron deficient heteroarenes with terminalalkynes is reported. The method relies on oxidative cleavage of phenylacetylenes for generation of acylradicals as a key enabling feature. The reaction is regioselective with broad substrate scope. Quantum yield investigations support a radical chain mechanism.
The fluoride ion effect in the reactions of singlet oxygen with enols
作者:Harry H. Wasserman、James E. Pickett
DOI:10.1016/s0040-4020(01)96587-1
日期:——
The fluoride ion effect in the reactions of enolic systems with singletoxygen has been investigated. β-Dicarbonyl compounds yielded 1,2,3-tricarbonyl derivatives, some of which underwent further hydration, whereas α-diketones suffered oxidative decarboxylation to give open-chain aldehydo-acids or keto-acids.
Isobutyl Nitrite-Mediated Synthesis of Quinoxalines through Double C−H Bond Amination of <i>N</i>
-Aryl Enamines
作者:Yan-Xiao Jiao、Lin-Su Wei、Chun-Yang Zhao、Kai Wei、Dong-Liang Mo、Cheng-Xue Pan、Gui-Fa Su
DOI:10.1002/adsc.201800928
日期:2018.11.16
An efficient and metal‐free double C−H bond amination of N‐aryl enamines using isobutyl nitrite (IBN) has been developed. This method enables the preparation of functionalized quinoxalines in good to excellent yields and tolerates a variety of N‐aryl enamines with diverse functional substituents. Mechanistic studies revealed the presence of a key β‐imino oxime ester intermediate. A quinoxaline derivative