在没有碱的情况下,使用NIS试剂通过分子内亲电环化到炔烃上,从2-炔基喹啉3-羧醛中制得了一种简单,温和的合成碘代1 H-吡喃并[4,3- b ]喹啉的简单方法在短时间内获得出色的产量。反应在室温下于普通溶剂中在有氧气氛中顺利进行。喹啉或炔基部分上取代基的存在对环化反应速率没有影响。还讨论了钯催化的碘基向C–C键的转化。
Azidation vs [3 + 2]-cycloaddition: Chemoselective reaction of sodium azide towards o-alkynylaldehydes for the synthesis of N-heterocycles
作者:Pradeep Kumar、Vineeta Garg、Akhilesh K. Verma
DOI:10.1016/j.tetlet.2019.06.022
日期:2019.7
The chemoselective synthesis of functionalized azido- and triazolo-containing nitrogen heterocycles using sodium azide and o-alkynylaldehydes has been described. The azidation reaction was preferred in acetonitrile while the [3 + 2]-cycloaddition was favored in DMSO. Furthermore, the azido-pyranoquinolines were employed for the synthesis of benzonaphthyridines via the Staudinger reaction at room temperature
Na2S·9H2O mediated facile synthesis of 1,3-dihydrofuro[3,4-b]quinoline derivatives via domino reduction approach
作者:Rashmi Singh、Tanu Gupta、Vishal Prasad Sharma、Radhey M. Singh、Ashish Kumar Tewari
DOI:10.1016/j.tet.2021.132447
日期:2021.10
A simple, highly efficient method for synthesis of 1,3-dihydrofuro[3,4-b]quinoline is described by the reaction of o-arylalkynyl quinoline aldehydes with Na2S·9H2O via domino reduction approach. The method is simple and proceeds under mild condition under an air atmosphere to give 1,3-dihydrofuro[3,4-b]quinoline in good to excellent yields. The beauty of the reaction is cyclization as well as reduction
邻芳炔基喹啉醛与Na 2 S·9H 2 O通过多米诺还原法反应,描述了一种简单、高效的合成1,3-二氢呋喃[3,4- b ]喹啉的方法。该方法简单,在温和条件下,在空气气氛下进行,以良好至极好的收率得到1,3-二氢呋喃[3,4- b ]喹啉。该反应的美妙之处在于在同一个反应釜中进行了环化和还原。在相同的反应条件下也讨论了醛向伯醇的转化。
Chemoselective Azidation of <i>o</i>-Alkynylaldehydes over [3 + 2] Cycloaddition and Subsequent Staudinger Reaction: Access to Benzonaphthyridines/Naphthyridines
作者:Pradeep Kumar、Trapti Aggarwal、Akhilesh K. Verma
DOI:10.1021/acs.joc.7b01016
日期:2017.6.16
conditions is described. Mechanisticstudies confirm the formation of azido-pyranoquinolines through nucleophilic attack of azide on pyrilium intermediate over [3 + 2] cycloaddition of the azide on the alkyne. The synthesized azido-pyranoquinolines were transformed into benzonaphthyridines via Staudinger reaction. The mechanistic pathway was supported by deuterium labeling experiment and X-ray crystallographic
Unveiling the Three-Component Phosphonylation on Alkynylaldehydes: Toolbox toward Fluorescent Molecules
作者:Deepika Thakur、Trapti Aggarwal、Muskan、Sushmita、Akhilesh K. Verma
DOI:10.1021/acs.joc.2c02915
日期:2023.2.17
A regioselective tandem approach for annulated napthyridines/isoquinolines embedded with the phosphine oxide group under mild reaction conditions has been achieved in good to excellent yields. The designed strategy involves the triflate-induced formation of new C sp3–P and C sp2–N bondformation in one pot. This protocol was also well tolerated for the construction of densely functionalized organo-phosphorylated
在温和的反应条件下,已经实现了一种区域选择性串联方法,用于嵌入氧化膦基团的环状萘啶/异喹啉,收率良好。设计的策略涉及三氟甲磺酸诱导在一个锅中形成新的 C sp 3 -P 和 C sp 2 -N 键。该协议对于以良好的产量构建密集功能化的有机磷酸化色烯也具有很好的耐受性。此外,膦衍生的磺胺二甲嘧啶和磺胺甲恶唑药物也以良好的收率成功合成。机理研究表明,离子通路和区域选择性6-内切酶的形成通过 X 射线晶体学研究证实了环化产物。有趣的是,选择性化合物的光物理研究揭示了它们的激发荧光特性。
An economical nucleophilic route toward facile synthesis of pyrano[4,3-b]quinolin-1-ones via 6-endo-dig cyclization of o-alkynylquinoline esters
作者:Neha Sharma、Mrityunjaya Asthana、Durgesh Nandini、R.P. Singh、Radhey M. Singh
DOI:10.1016/j.tet.2012.12.068
日期:2013.2
Metal-free facile synthesis of pyrano[4,3-b]quinoline-1-ones is described from methyl 2-arylethynyl-quinoline-3-carboxylates via intramolecular cyclization in excellent yields. The cyclization reactions are facilitated using cheap and easily available KOH base in MeOH. The reaction conditions did not require dry solvent, inert atmosphere, and avoid further column chromatography purification of the products. These compounds could be further used as building blocks for the synthesis of 2H-benzo[b][1,6]naphthyridin-1-one and 1-chloro-benzo[b][1,6]naphthyridines. (C) 2013 Elsevier Ltd. All rights reserved.