Visible-Light-Promoted Photocatalyst-Free Hydroacylation and Diacylation of Alkenes Tuned by NiCl<sub>2</sub>·DME
作者:Xinxin Zhao、Bing Li、Wujiong Xia
DOI:10.1021/acs.orglett.9b04595
日期:2020.2.7
4-dihydropyridines via an acyl radical addition and hydrogen atom transfer pathway under photocatalyst-free conditions. The efficiency was highlighted by wide substrate scope, good to high yields, successful scale-up experiments, and expedient preparation of highly functionalized ketone derivatives. In addition, this protocol allows for the synthesis of 1,4-dicarbonyl compounds through alkene diacylation in the presence
Acyl Radicals from α-Keto Acids Using a Carbonyl Photocatalyst: Photoredox-Catalyzed Synthesis of Ketones
作者:Da-Liang Zhu、Qi Wu、David James Young、Hao Wang、Zhi-Gang Ren、Hong-Xi Li
DOI:10.1021/acs.orglett.0c02351
日期:2020.9.4
Acylradicals have been generated from α-keto acids using inexpensive and commercially available 2-chloro-thioxanthen-9-one as the photoredox catalyst under visible light illumination. These reactive species added to olefins or coupled with aryl halides via a bipyridyl-stabilized Ni(II) catalyst, enabling easy access to a diverse range of ketones. This reliable, atom-economical, and eco-friendly protocol
Nitrone Cycloadditions to 1,2-Diphenylcyclopropenes and Subsequent Transformations of the Isoxazolidine Cycloadducts
作者:Vyacheslav V. Diev、Oksana N. Stetsenko、Tran Q. Tung、Jürgen Kopf、Rafael R. Kostikov、Alexander P. Molchanov
DOI:10.1021/jo702379d
日期:2008.3.1
occurs with the formation of expected “normal” cycloadducts (with N-methylnitrones) and products of their subsequent transformations. Among them are corresponding α-acetophenyl aziridines and tetra (or penta) -arylpyrroles. Aziridines and the normal cycloadducts can be also thermally converted to such arylpyrroles with moderate to good yields. Substitution at the C3 position of cyclopropenes by an electron
Synthesis of Tetrasubstituted Pyrroles from Homopropargylic Amines<i>via</i>a Sonogashira Coupling/Intramolecular Hydroamination/Oxidation Sequence
作者:Chan Wang、Kaimeng Huang、Junying Wang、Hongkai Wang、Lingyan Liu、Weixing Chang、Jing Li
DOI:10.1002/adsc.201500350
日期:2015.9.14
A one‐pot reaction of homopropargylic amines and aryl iodides was developed in the presence of a palladium (Pd) catalyst and generated a series of tetrasubstitutedpyrrole derivatives in good to high yields. This process involved a Sonogashira, intramolecularhydroamination, cyclization and oxidationsequence of reactions.
An Efficient Synthesis of Substituted Pyrroles with the Aid of a Low-Valent Titanium Reagent
作者:Daqing Shi、Chuling Shi、Xiangshan Wang、Qiya Zhuang、Shujiang Tu、Hongwen Hu
DOI:10.1055/s-2004-831295
日期:——
A short and efficientsynthesis of substituted pyrroles was accomplished in good yields via the novel coupling cyclization reaction of 1,3-diketones with imines or oximes promoted by TiCl 4 / Zn system.