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。
Base-free NIS promoted electrophilic cyclization of alkynes: an efficient synthesis of iodo substituted pyrano[4,3-b]quinolines
作者:Bhawana Singh、Atish Chandra、Seema Singh、Radhey M. Singh
DOI:10.1016/j.tet.2010.10.081
日期:2011.1
A simple and mild procedure for the synthesis of iodo substituted 1H-pyrano[4,3-b]quinolines has been achieved using NIS reagent in the absence of base from 2-alkynylquinoline-3-carboxaldehydes via intramolecular electrophiliccyclization onto alkynes in good to excellent yields in a short duration of time. The reactions proceeded smoothly in a normal solvent in aerobic atmosphere at room temperature
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。
Copper-free Sonogashira coupling of 2-chloroquinolines with phenyl acetylene and quick annulation to benzo[b][1,6]naphthyridine derivatives in aqueous ammonia
作者:Atish Chandra、Bhawana Singh、Shraddha Upadhyay、Radhey M. Singh
DOI:10.1016/j.tet.2008.10.010
日期:2008.12
An efficient copper-freeSonogashiracoupling of 2-chloroquinolines with phenyl acetylene to 2-ethynylquinolines is described. We further discussed the one pot facile annulation of 2-alkynylquinoline-3-carboxaldehydes to 3-phenylbenzo[b][1,6]naphthyridines in aqueous ammonia in excellent yield.
描述了2-氯喹啉与苯基乙炔到2-乙炔基喹啉的有效的无铜Sonogashira偶联。我们进一步讨论了在氨水中,2-炔基喹啉-3-甲醛与3-苯基苯并[ b ] [1,6]萘啶的一锅法环氧化反应,收率很好。
Cu(I)-Catalyzed Oxygen and Nitrogen Nucleophiles Triggered Regioselective Synthesis of Furo/Pyrrolo-Annulated Quinolines
作者:Ritush Kumar、Atish Chandra、Bilal Ahmad Mir、Gaurav Shukla
DOI:10.1021/acs.joc.9b00662
日期:2019.9.6
Cu(I)-catalyzedintramolecularannulation of o-ethynylquinoline-3-carbaldehydes leads to the synthesis of alkoxy/imidazole-substituted 1,3-dihydrofuro[3,4-b]quinolines via C–O and C–N bond formation. The scope of the reaction was further extended to o-ethynylquinoline-3-carbonitriles for the synthesis of alkoxy-substituted 3H-pyrrolo[3,4-b]quinolines using alcohols as nucleophiles. These reactions
Cu(I) 催化的o -ethynylquinoline-3-carbaldehydes 的分子内环化导致通过 C-O 和 C-N 键的形成合成烷氧基/咪唑取代的 1,3-二氢呋喃[3,4- b ] 喹啉。该反应的范围进一步扩展到邻乙炔基喹啉-3-腈,用于使用醇作为亲核试剂合成烷氧基取代的 3 H-吡咯并[3,4- b ]喹啉。这些反应区域选择性地有利于所有环化过程中的 5 -exo-dig环化。
Catalytic trifluoromethylation of aldehyde and potential application for pyrano[4,3-b]quionline synthesis
作者:Kalpana Mishra、Kishor Chandra Bharadwaj、Radhey M. Singh
DOI:10.1016/j.tetlet.2018.08.012
日期:2018.9
heteroaromatic aldehydes at room temperature to afford trifluoromethyl group containing alcohols in very good yields. Using catalytic amount of CsF (0.2 eq.) in toluene, trifluoromethylated products were achieved in good yields at rt. The substrate scope has been exemplified by a large number of substrates. As an application, iodo etherification/cyclization has also been demonstrated for the synthesis of trifluoromethyl
我们已经描述了在室温下CsF催化的杂芳族醛的三氟甲基化以非常好的收率得到含三氟甲基的醇。使用在甲苯中的催化量的CsF(0.2当量),在室温下以良好的产率获得了三氟甲基化的产物。基板范围已经以大量基板为例。作为一种应用,碘醚化/环化也已被证明可以非常好地由邻炔基三氟甲醇合成三氟甲基吡喃并[4,3- b ]喹啉。
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.