Visible-Light Photoredox Catalyzed Three-Component Cyclization of 2H-Azirines, Alkynyl Bromides, and Molecular Oxygen to Oxazole Skeleton
摘要:
A novel three-component cyclization of 2H-azirines, alkynyl bromides, and molecular oxygen under visible light photoredox catalysis at room temperature has been developed, which provides a direct approach to a wide range of substituted oxazoles in moderate to good yields.
开发了一种新的、简单有效的合成1-oxa-4-aza-spirooxazolines的方法。该反应在室温下使用玫瑰红作为有机光氧化还原催化剂和蓝色 LED 作为光源进行。据观察,醌与叠氮乙烯在 CO 双键而不是 CC 双键上发生螺环化反应,通过该反应,各种相应的各种相应的 1-oxa-4-aza-spirooxazolines 以良好至优异的产率合成。
Electrochemical Synthesis of
<i>O</i>
‐Phthalimide Oximes from
<i>α</i>
‐Azido Styrenes
<i>via</i>
Radical Sequence: Generation, Addition and Recombination of Imide‐
<i>N</i>
‐Oxyl and Iminyl Radicals with C−O/N−O Bonds Formation
作者:Stanislav A. Paveliev、Artem I. Churakov、Liliya S. Alimkhanova、Oleg O. Segida、Gennady I. Nikishin、Alexander O. Terent'ev
DOI:10.1002/adsc.202000618
日期:2020.9.21
Electrochemically induced radical‐initiated reaction of vinyl azides with N‐hydroxyphthalimide resulting O‐phthalimide oximes with challenging for organic chemistry N−O‐N fragment has been discovered. The developed approach introduces in synthesis electrochemically generated O‐centered imide‐N‐oxyl radicals as the coupling components. Sequential formation of C−O and N−O bonds was achieved via generation
I<sub>2</sub>-catalyzed synthesis of substituted imidazoles from vinyl azides and benzylamines
作者:Likui Xiang、Yanning Niu、Xiaobo Pang、Xiaodong Yang、Rulong Yan
DOI:10.1039/c5cc01155h
日期:——
A novel and efficient I2-catalyzed oxidative tandem cyclization of simple vinyl azides and benzylamines has been developed for the synthesis of substituted imidazoles.
一种新颖高效的I2催化的氧化串联环化反应已经开发出来,用于合成取代咪唑。
Azide–Enolate Cycloaddition‐Rearrangement Enables Direct α‐Amination of Amides and Enelactam Synthesis from Esters**
作者:Joseph J. Bell‐Tyrer、Paul A. Hume、Phillip S. Grant、Margaret A. Brimble、Daniel P. Furkert
DOI:10.1002/chem.202300261
日期:——
Diverse frameworks via cycloaddition-rearrangement: Azide-enolate cycloaddition-rearrangements were applied to the direct α-amination of amides and lactams, and synthesis of ene-γ-lactams fromesters. The outcome of the reaction varied by substrate, depending on the fate of triazoline intermediates generated in the cycloaddition. These processes form part of a wider cycloaddition-rearrangement reaction
Visible-Light-Induced Regioselective C(sp<sup>3</sup>)-H Acyloxylation of Aryl-2<i>H-</i>azirines with (Diacetoxy)iodobenzene
作者:Aramita De、Sougata Santra、Alakananda Hajra、Grigory V. Zyryanov、Adinath Majee
DOI:10.1021/acs.joc.9b01625
日期:2019.9.20
A visible-light-promoted regioselective coupling of C(sp(3))-H of aryl-2H-azirine and (diacetoxy)-iodobenzene has been reported. Rose Bengal as an organo-photoredox catalyst has been used in this reaction. The reaction proceeds under aerobic condition at room temperature. A variety of aryl-2H-azirines gives the corresponding acyloxylated azirines under this reaction conditions. The reaction goes through a radical pathway. The protocol is also applicable on gram-scale synthesis.
Synthesis of thiazolidinimines/thiazinan-2-imines via three-component coupling of amines, <i>vic</i>-dihalides and isothiocyanates under metal-free conditions