本文中,我们描述了一种环境友好且具有成本效益的方案,用于合成有价值的呋喃二甲酸二羧酸酯,首先是通过LiBr和K 2 S 2 O 8对易得的呋喃-2-羧酸酯进行α-溴化反应。此外,然后在醇存在下,在钯催化的还原均偶联反应中进行溴化中间产物5-溴呋喃-2-羧酸酯的合成,得到双呋喃基二羧酸酯。该协议的最终产品之一,[2,2'] bifuran-5,5'-二羧酸酯是聚(呋喃二甲酸乙二酯)的重要单体,可用作传统聚对苯二甲酸乙二醇酯的绿色多用途替代聚合物。 (对苯二甲酸乙二醇酯)目前在工业塑料中很常见。
本文中,我们描述了一种环境友好且具有成本效益的方案,用于合成有价值的呋喃二甲酸二羧酸酯,首先是通过LiBr和K 2 S 2 O 8对易得的呋喃-2-羧酸酯进行α-溴化反应。此外,然后在醇存在下,在钯催化的还原均偶联反应中进行溴化中间产物5-溴呋喃-2-羧酸酯的合成,得到双呋喃基二羧酸酯。该协议的最终产品之一,[2,2'] bifuran-5,5'-二羧酸酯是聚(呋喃二甲酸乙二酯)的重要单体,可用作传统聚对苯二甲酸乙二醇酯的绿色多用途替代聚合物。 (对苯二甲酸乙二醇酯)目前在工业塑料中很常见。
Determination of aromaticity indices of thiophene and furan by nuclear magnetic resonance spectroscopic analysis of their phenyl esters
作者:Chang Kiu Lee、Ji Sook Yu、Hye-Jin Lee
DOI:10.1002/jhet.5570390615
日期:2002.11
series of m- and p-substituted phenyl benzoates, 2-thienoates, and 2-furoates were prepared and their 1H and 13C nmr spectroscopic characteristics were examined. In general, good correlations were observed between the chemical shift values of protons and carbons of the acyl aromatic rings and the Hammett σ. Plots of the chemical shift values of the carbonyl carbons of the benzoates against those of
To explore further the practical uses of highly active manganese (Mn*), a variety of alcohols were treated with Mn*, and the resulting complexes were coupled with acid chlorides and/or acetic anhydride in the absence of any extra catalyst. The subsequent reactions took place smoothly under mild conditions, providing the corresponding O-acylation products in good to excellent isolated yields.
Palladium-Catalyzed C–H Benzannulation of Functionalized Furans and Pyrroles with Alkynes
作者:Jia Seo、Che-Wei Chen、Shih-Ching Chuang、Jung Min Joo、Woohyeong Lee、Ju Eun Jeon、Pei-Ling Chen
DOI:10.1055/a-1502-3641
日期:2021.9
A benzannulation strategy involving activation of two C–H bonds of five-membered heteroarenes was developed. Readily available furans and pyrroles stabilized by synthetically useful electron-withdrawing groups underwent Pd-catalyzed 1:2 annulation reactions with diaryl alkynes. A variety of functional groups, including ester, amide, ketone, aldehyde, and nitrile, on the heterocyclic cores were tolerated
three components (i.e., heteroarene, alcohol, and CHCl3). The copper additive was confirmed to simultaneously promote the reaction in three pathways: oxidant cracking, single electron transfer, and alcoholysis. By means of this protocol, various functionalized furancarboxylates and other heteroarenecarboxylates were facilely obtained in moderate to good yields.
Study of<i>cis/trans</i>and<i>endo/exo</i>Diastereoselectivity in the [4+3]-Cycloaddition Reaction of 2-Functionalized Furans and Dimethyloxyallyl Cation: Preparation of Versatile Cycloheptane Synthons
作者:Angel M. Montaña、Sandra Ribes、Pedro M. Grima、Francisca García
DOI:10.1246/cl.1997.847
日期:1997.9
A study on the influence of steric and electronic effects of a function attached at C-2 of furans in the yield and diastereoselectivity of [4+3] cycloaddition reactions with oxyallyl cations is presented. In almost all studied furans a cis diastereospecificity and a high endo diastereoselectivity is observed. Increasing bulkyness of the function attached at C-2 of furans, increases the endo diastereoselectivity, but decreases yield. Increasing the electronic density of the furan system, by an electron donating group attached at C-2, increases yield and diastereoselectivity.