New and Efficient Palladium(0)-Mediated Microwave-Assisted Direct C3 Alkenylation of Imidazo[1,2-<i>a</i>]pyridines
作者:Sabine Berteina-Raboin、Jamal Koubachi、Saïd El Kazzouli、Abderrahim Mouaddib、Gérald Guillaumet
DOI:10.1055/s-2008-1067181
日期:2008.8
2-a]pyridines in high to moderate yields by microwave direct palladium-catalyzed C-H alkenylation between bromoalkenes and imidazo[1,2-a]pyridines. The scope and limitation of the palladium(0)-catalyzed alkenylation method were investigated. Optimized conditions were successfully applied to a wide variety of imidazo[1,2-a]pyridine derivatives and bromoalkenes. The compatibility of the synthesis with
On the mechanism of the direct acid catalyzed formation of 2,3-disubstituted imidazo[1,2-a]pyridines from 2-aminopyridines and acetophenones. Concurrence between ketimine and Ortoleva–King type reaction intermediated transformations
作者:Vanya B. Kurteva、Lubomir A. Lubenov、Daniela V. Antonova
DOI:10.1039/c3ra45005h
日期:——
Direct acid catalyzed formation of 2,3-disubstitutedimidazo[1,2-a]pyridines from 2-aminopyridines and acetophenones was studied in order to gain insight into the reaction mechanism. The formation of differently substituted products was explained by a concurrent ketimine and Ortoleva–King type reaction intermediated transformations. The dependence of the reaction output on the catalyst used and on
为了直接了解反应机理,研究了由2-氨基吡啶和苯乙酮直接酸催化形成2,3-二取代的咪唑并[1,2- a ]吡啶。并发的酮亚胺和Ortoleva-King型反应中间转化同时解释了取代基不同的产物的形成。讨论了反应输出对所用催化剂以及对苯乙酮和吡啶取代基的依赖性。
Palladium(<scp>ii</scp>)-catalyzed intermolecular oxidative C-3 alkenylations of imidazo[1,2-a]pyridines by substrate-contolled regioselective C–H functionalization
An efficient and highlyregioselective palladium(II)-catalyzed oxidative C-3alkenylation of imidazo[1,2-a]pyridines with acrylate, acrylonitrile, or vinylarenes has been developed by using oxygen as an oxidant. Substrates such as acrylate and acrylonitrile tended to form β-product, while vinylarenes tended to form the sole α-products.
通过使用氧气作为氧化剂,已经开发出了一种高效且高度区域选择性的钯(II)催化的咪唑并[1,2- a ]吡啶与丙烯酸酯,丙烯腈或乙烯基芳烃的氧化C-3烯基化反应。诸如丙烯酸酯和丙烯腈之类的底物倾向于形成β-产物,而乙烯基芳烃则倾向于形成唯一的α-产物。
Fast and efficient direct conversion of 2-aminopyridine into 2,3-disubstituted imidazo[1,2-a]pyridines
作者:Vanya B. Kurteva、Lubomir A. Lubenov、Daniela V. Nedeltcheva、Rositsa P. Nikolova、Boris L. Shivachev
DOI:10.3998/ark.5550190.0013.824
日期:——
A directconversion of 2-aminopyridine into 2,3-disubstitutedimidazo[1,2-a]pyridines was studied. A series of products was obtained in an efficient, simple and fast protocol. The scope and limitation of the transformation are also studied and was found that its effectiveness and the type of the substituent at 3-position, 3-(1-arylethane) and/or 3-(1-arylethene), is strongly dependent both on the catalyst
intermolecular oxidative coupling of imidazo[1,2-a]pyridines with alkenes was successfully developed. The scope and limitations of the reaction were further studied by using various alkenes. This method provides a ‘green’ route to 3-alkenylimidazo[1,2-a]pyridine derivatives in high yields. palladium/copper-catalyzed oxidative coupling - alkenylation - imidazo[1,2-a]pyridines
成功开发了一种新型的直接和区域选择性的Pd / Cu催化的咪唑并[1,2- a ]吡啶与烯烃的分子间氧化偶联。通过使用各种烯烃进一步研究了反应的范围和局限性。该方法提供了高收率的3-烯基咪唑并[1,2- a ]吡啶衍生物的“绿色”路线。 钯/铜催化的氧化偶合-烯基化-咪唑并[1,2- a ]吡啶