Rhodium‐Catalyzed C−H Activation‐Based Construction of Axially and Centrally Chiral Indenes through Two Discrete Insertions
作者:Fen Wang、Jierui Jing、Yanliang Zhao、Xiaohan Zhu、Xue‐Peng Zhang、Liujie Zhao、Panjie Hu、Wei‐Qiao Deng、Xingwei Li
DOI:10.1002/anie.202105093
日期:2021.7.19
Reported herein is asymmetric [3+2] annulation of arylnitrones with different classes of alkynes catalyzed by chiralrhodium(III) complexes, with the nitrone acting as an electrophilic directing group. Three classes of chiral indenes/indenones have been effectively constructed, depending on the nature of the substrates. The coupling system features mild reaction conditions, excellent enantioselectivity
Accessing benzooxadiazepines<i>via</i>formal [4 + 3] cycloadditions of aza-<i>o</i>-quinone methides with nitrones
作者:Yong-Sheng Zheng、Liang Tu、Li-Mei Gao、Rong Huang、Tao Feng、Huan Sun、Wen-Xuan Wang、Zheng-Hui Li、Ji-Kai Liu
DOI:10.1039/c8ob00201k
日期:——
An unprecedented and efficient [4 + 3] cycloaddition of N-(ortho-chloromethyl)aryl amides with nitrones has been developed. This approach provides easy access to a series of seven-membered benzooxadiazepine derivatives in good to excellent yields (up to 99% yield) under mild reaction conditions.
selective and efficient reagent for the oxidation of hydroxylamines. The developed reaction conditions were shown to be compatible with the in situ trapping of the produced nitrones by a strained alkyne, via a [3 + 2] cycloaddition reaction.
α,β‐Unsaturated Amides as Dipolarophiles: Catalytic Asymmetric
<i>exo</i>
‐Selective 1,3‐Dipolar Cycloaddition with Nitrones
作者:Ming Zhang、Naoya Kumagai、Masakatsu Shibasaki
DOI:10.1002/chem.201702330
日期:2017.9.12
1,3-Dipolarcycloaddition is a commonly exploited method to access 5-membered chemical entities with a variety of peripheral functionalities and their stereochemical arrangements. Nitrones are isolable 1,3-dipoles that exhibit sufficient reactivity toward electron-deficient olefins in the presence of Lewis acids to deliver highly substituted isoxazolidines. Herein we document that α,β-unsaturated amides
Synthesis of α-Amino Acids through Samarium(II) Iodide Promoted Reductive Coupling of Nitrones with CO2
作者:Alexander Prikhod'ko、Olaf Walter、Thomas A. Zevaco、Jaime Garcia-Rodriguez、Omar Mouhtady、Sandrine Py
DOI:10.1002/ejoc.201200440
日期:2012.7
Several N-benzylnitrones reacted with carbon dioxide in the presence of samarium(II) iodide leading to α-aminoacids as the products of reductive C–C coupling. The best selectivities were observed at a carbon dioxide pressure of 50 bar at ambient temperature. The influences of different functional
几种 N-苄基硝酮在碘化钐 (II) 存在下与二氧化碳反应,生成 α-氨基酸,作为还原性 C-C 偶联的产物。在环境温度和 50 巴的二氧化碳压力下观察到最佳选择性。不同功能的影响