Identification of a Novel Michael Acceptor Group for the Reversible Addition of Oxygen- and Sulfur-Based Nucleophiles. Synthesis and Reactivity of the 3-Alkylidene-3<i>H</i>-indole 1-Oxide Function of Avrainvillamide
作者:Andrew G. Myers、Seth B. Herzon
DOI:10.1021/ja0372006
日期:2003.10.1
The 3-alkylidene-3H-indole 1-oxide functional group found in the naturally occurring alkaloid avrainvillamide has been synthesized by a cross coupling-reductive condensation sequence and found to undergo reversible addition of oxygen- and sulfur-based nucleophiles.
Stereoselective Synthesis of Fluoroalkenoates and Fluorinated Isoxazolidinones: N-Substituents Governing the Dual Reactivity of Nitrones
作者:G. K. Surya Prakash、Zhe Zhang、Fang Wang、Martin Rahm、Chuanfa Ni、Marc Iuliucci、Ralf Haiges、George A. Olah
DOI:10.1002/chem.201303509
日期:2014.1.13
α‐Fluoroalkenoates and 4‐fluoro‐5‐isoxazolidinones are of vast interest due to their potential biological applications. We now demonstrate the syntheses of (E)‐α‐fluoroalkenoates and 4‐fluoro‐5‐isoxazolidinones by the reactions between nitrones and α‐fluoro‐α‐bromoacetate. By altering N‐substituents in nitrones, (E)‐α‐fluoroalkenoates and 4‐fluoro‐5‐isoxazolidinones can be achieved, respectively, with
all-carbon 1,4-dipoles could be generated selectively from the gold(I)-catalyzed cycloisomerizations of allenyl ketones bearing a cyclopropyl moiety, which undergo [4 + 3] cycloadditions with nitrones to produce two regiomers of furan-condensed N,O-seven-membered rings in moderate to excellent yields highly selectively.
Iridium-Catalyzed Redox-Neutral C2 and C3 Dual C–H Functionalization of Indoles with Nitrones toward 7<i>H</i>-Indolo[2,3-<i>c</i>]quinolines
作者:Miao Li、Yaqun Dong、Cong Zhou、Junxue Bai、Jiang Cheng、Jianwei Sun、Song Sun
DOI:10.1021/acs.orglett.1c02975
日期:2021.11.5
An iridium-catalyzed redox-neutral C-2 and C-3 dualC–Hfunctionalization of indoles with nitrones has been developed, furnishing a range of 7H-indolo[2,3-c]quinolines with high efficiency and regioselectivity under mild reaction conditions. Notably, sequential multiple C–H bond cleavage and C–C bond formation constitute the key events of this process, in which nitrone serves as a building block and
已开发出铱催化氧化还原中性 C-2 和 C-3 双 C-H 官能化吲哚与硝酮,提供一系列 7 H-吲哚[2,3- c ]喹啉,在温和的条件下具有高效率和区域选择性反应条件。值得注意的是,连续的多重 C-H 键断裂和 C-C 键形成构成了该过程的关键事件,其中硝酮作为构建块和氧化剂。与之前的 7 H-吲哚并[2,3- c ]喹啉方法不同,这种新开发的反应具有容易获得的底物、操作简单、范围广、效率高到高和优异的区域选择性。
Synthesis of <i>N</i>‐Aryl Isoxazolidines by Photo‐Promoted <i>N</i>‐Selective Arylation of Oximes and Cyclization Using Hypervalent Iodine Reagents and Copper Catalyst
corresponding N-aryl isoxazolidines in 26–95% yields. This method offers a faster reaction rate, lower catalyst loading and broader substrate scope of oxime than similar nitrone syntheses employing Chan-Lam-Evanscoupling. The reaction involves via a radical/single electron transfer (SET) pathway, and does not proceed in the absence of photoirradiation.