Photocatalytic decarboxylative alkylations mediated by triphenylphosphine and sodium iodide
作者:Ming-Chen Fu、Rui Shang、Bin Zhao、Bing Wang、Yao Fu
DOI:10.1126/science.aav3200
日期:2019.3.29
variety of alkylations. Science, this issue p. 1429 A cheap combination of sodium iodide and triphenylphosphine can act as an electron-transfer catalyst under visible light. Most photoredox catalysts in current use are precious metalcomplexes or synthetically elaborate organic dyes, the cost of which can impede their application for large-scale industrial processes. We found that a combination of triphenylphosphine
Synthesis of 3-Fluoropyridines via Photoredox-Mediated Coupling of α,α-Difluoro-β-iodoketones with Silyl Enol Ethers
作者:Sofya I. Scherbinina、Oleg V. Fedorov、Vitalij V. Levin、Vladimir A. Kokorekin、Marina I. Struchkova、Alexander D. Dilman
DOI:10.1021/acs.joc.7b02467
日期:2017.12.15
A method for the synthesis of diversely substituted 3-fluoropyridines from two ketone components is described. The reaction involves photoredox coupling of α,α-difluoro-β-iodoketones with silyl enol etherscatalyzed by fac-Ir(ppy)3 under blue LED irradiation with subsequent one-pot condensation with ammonium acetate. Based on cyclic voltammetry studies, it was determined that α,α-difluoro-β-iodoketones
Photoredox-Catalyzed Generation of Sulfamyl Radicals: Sulfonamidation of Enol Silyl Ether with Chlorosulfonamide
作者:Qiyu Luo、Runyu Mao、Yan Zhu、Yonghui Wang
DOI:10.1021/acs.joc.9b02062
日期:2019.11.1
A novel and practical photoredox-catalyzed generation of sulfamyl radicals followed by radical sulfonamidation of enolsilylether has been described. Diverse functionalized β-ketosulfonamides were prepared in modest to excellent yields under mild and economic reaction conditions through the present catalytic protocol. Furthermore, the methodology developed provides an efficient and convenient approach
Direct synthesis of 2-arylazulenes by [8+2] cycloaddition of 2<i>H</i>-cyclohepta[<i>b</i>]furan-2-ones with silyl enol ethers
作者:Taku Shoji、Shuhei Sugiyama、Yoshiaki Kobayashi、Akari Yamazaki、Yukino Ariga、Ryuzi Katoh、Hiroki Wakui、Masafumi Yasunami、Shunji Ito
DOI:10.1039/c9cc09376a
日期:——
We developed a procedure for the direct synthesis of 2-arylazulenes, which were obtained in moderate to excellent yields, by [8+2] cycloaddition of 2H-cyclohepta[b]furan-2-ones with aryl-substituted silylenolethers. The structures of some 2-arylazulenes were clarified by single-crystal X-ray analysis. The 2-phenylazulene derivatives obtained by this study showed noticeable fluorescence in acidic
Photoredox-catalyzed silyldifluoromethylation of silyl enol ethers
作者:Vyacheslav I Supranovich、Vitalij V Levin、Alexander D Dilman
DOI:10.3762/bjoc.16.126
日期:——
light-mediated fluoroalkylation of silyl enol ethers with (bromodifluoromethyl)trimethylsilane followed by a reduction of the primary products with sodium borohydride is described. An 18 W, 375 nm LED was used as the light source. The reaction is performed in the presence of a gold photocatalyst, which effects the generation of a (trimethylsilyl)difluoromethyl radical via cleavage of the carbon–bromine