Synthesis of cyclopentaquinolinone and cyclopentapyridinone from <i>ortho</i>-alkynyl-<i>N</i>-arylaldehyde <i>via</i> superbase-promoted C–N, C–O and C–C bond formation
作者:Kapil Mohan Saini、Rakesh K. Saunthwal、Sushmita、Akhilesh K. Verma
DOI:10.1039/d0ob01281e
日期:——
and cyclopentapyridinones via C–N, C–C, and CO bond formation. Contrary to the traditional approaches of ringclosures, a different mode of annulation is disclosed. The protocol involves the in situ generations of imine intermediate followed by potassium hydroxide-promoted intramolecular cyclization and subsequent dimethyl sulfoxide induced dehydrogenation leads to the formation of N-heterocycles. X-ray
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。
Metal-free POCl<sub>3</sub> promoted stereoselective hydrochlorination of ethynylated azaheterocycles
作者:Ritush Kumar、Radhey M. Singh
DOI:10.1039/c9ob00841a
日期:——
POCl3 as a chlorinating agent under metal-free reaction conditions. Mechanistic studies show that the reaction proceeded via nucleophilic attack of POCl3 on the nitrogen of the quinoline ring in a stereoselective manner. The resulting products were versatile intermediates in organic synthesis and were used in the cross-coupling reaction and metal-free synthesis of heterocycles. The developed protocol features
TBHP-promoted oxidative cyclization of o-alkynylquinoline aldehydes: Metal/additive-free domino synthesis of pyrano[4,3-b]quinolin-1-ones
作者:Jay Bahadur Singh、Kalpana Mishra、Tanu Gupta、Radhey M. Singh
DOI:10.1016/j.tetlet.2018.01.083
日期:2018.3
TBHP-promoted domino synthesis of pyrano[4,3-b]quinolin-1-ones is described from o-alkynylquinoline aldehydes. The radical reaction proceeded without metal and additive via oxidation of aldehydic C-H bond into C-OH bond followed by intramolecular 6-endo-dig cyclization. The probable mechanism is discussed.
由邻炔基喹啉醛描述了TBHP促进的吡喃并[4,3 - b ]喹啉-1-酮的多米诺合成。自由基反应是在没有金属和添加剂的情况下进行的,方法是将醛键的CH键氧化为C-OH键,然后进行分子内6-内切环化。讨论了可能的机制。
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。