Copper-catalyzed direct synthesis of furans and thiophenes via decarboxylative coupling of alkynyl carboxylic acids with H2O or Na2S
摘要:
2,5-Diaryl-substituted furans were synthesized from the copper-catalyzed decarboxylative coupling of aryl-substituted aryl propiolic acids in the presence of H2O. The homocoupling of alkynyl carboxylic acids provided 1,4-diaryldiynes, which then reacted with H2O to give the desired furans through cyclization. Addition of the copper catalyst was critical, and the addition of a ligand increased the yield of products in both the homocoupling and cyclization reactions. In addition, thiophenes could be obtained when the reaction was conducted in the presence of Na2S. (C) 2015 Elsevier Ltd. All rights reserved.
Radical Arylation of Phenols, Phenyl Ethers, and Furans
作者:Alexander Wetzel、Gerald Pratsch、Roman Kolb、Markus R. Heinrich
DOI:10.1002/chem.200902927
日期:2010.2.22
efficient, and cost‐effective new access to diversely functionalized biphenyl alcohols and ethers. Free phenolic hydroxy groups, aromatic and aliphatic amines, as well as amino acid substructures, are well tolerated. Two examples for the applicability of the methodology are the partialsynthesis of a β‐secretase inhibitor and the synthesis of a calcium‐channel modulator.
Ionic Liquid as Catalyst and Reaction Medium: A Simple and Efficient Procedure for Paal–Knorr Furan Synthesis
作者:Gangqiang Wang、Zhi Guan、Rongchang Tang、Yanhong He
DOI:10.1080/00397910902978049
日期:2010.1.14
The ionicliquid 1-butyl-3-methyl-imidazolium hydrogen sulfate, [bmim]HSO4, efficiently catalyzes Paal–Knorr furan synthesis without any organic solvent. A wide range of aliphatic and aromatic 1,4-diketones easily undergo condensations to form furan derivatives, providing a general and convenient procedure. The Paal–Knorr reaction of ester-substituted 1,4-diketones is first reported. The ionic liquid
A general and practical synthetic method for aryl-substituted five-membered heterocycles has been developed. In the presence of KOH (30%), 1,4-diaryl-1,3-butadiynes undergo the cyclocondensation reaction with water, primary amines, and Na2S·9H2O in DMSO at 80 °C to afford 2,5-diarylfurans, 1,2,5-trisubstituted pyrroles, and 2,5-diarylthiophenes in good to high yields. Further studies have disclosed
A New Facile Approach to the Synthesis of 3-Methylthio-Substituted Furans, Pyrroles, Thiophenes, and Related Derivatives
作者:Guodong Yin、Zihua Wang、Aihua Chen、Meng Gao、Anxin Wu、Yuanjiang Pan
DOI:10.1021/jo702585s
日期:2008.5.1
the Paal−Knorr furansynthesis. Meanwhile, 4-bromo-3-methylthio 2,5-diaryl furan 10 is obtained either by the treatment of furan 7 with molecular bromine or by the treatment of diketone 3 with 30% hydrogen bromide in acetic acid solution in one pot. Removal of the methylthio group is accomplished by the treatment of 7 with Raney Ni in ethanol, which affords the diaryl-substituted furan 11 in excellent
Copper(I)-Catalyzed Synthesis of 2,5-Disubstituted Furans and Thiophenes from Haloalkynes or 1,3-Diynes
作者:Huanfeng Jiang、Wei Zeng、Yibiao Li、Wanqing Wu、Liangbing Huang、Wei Fu
DOI:10.1021/jo300692d
日期:2012.6.1
A regioselective synthesis of 2,5-disubstitutedfurans using copper(I) catalyst from haloalkynes in a one-pot procedure has been reported. This chemistry proceeds through the hydration reaction of 1,3-diynes, which can be readily prepared from the coupling reaction of haloalkynes in the presence of CuI. The procedure also can be used for the facile synthesis of 2,5-disubstituted thiophenes.