A highly enantioselective organocatalytic conjugate addition of acetylacetone to 3-ylideneoxindoles is described. This method provides polysubstituted oxindoles in good to excellent enantioselectivities and high isolated yields.
Enantioselective Desymmetrization of Curcumins with 3‐Olefinic Oxindoles for the Synthesis of Spirocyclohexanoneoxindoles
作者:Chenikkayala Siva Sankara、Shweta Bhagat、Ajeet Chandra、Irishi N. N. Namboothiri
DOI:10.1002/ejoc.202300069
日期:——
Spiro-oxindoles containing three contiguous chiral centers were synthesized with excellent diastereo- and enantioselectivities via cascade double Michael reactions of curcumins with 3-alkylideneoxindole carboxylates. The selectivities are supported by transitions state energy calculations at B3LYP//6-31g(d) level of DFT.
Skeletal rearrangement through photocatalytic denitrogenation: access to C-3 aminoquinolin-2(1<i>H</i>)-ones
作者:Swati Singh、Gopal Chakrabortty、Sudipta Raha Roy
DOI:10.1039/d3sc04447e
日期:——
alternative method for the synthesis of 3-amino quinolin-2(1H)-one that overcomes the limitations of traditional methods by editing the molecular skeleton via a cascade C–N bond formation and denitrogenation process. We used TMSN3 as an aminating agent and a wide variety of 3-ylideneoxindoles as synthetic precursors for the quinolin-2(1H)-one backbone, which demonstrates remarkable tolerance of sensitive
将胺基添加到杂芳族系统中是一项具有挑战性的合成过程,但它是许多生物活性分子开发中必不可少的过程。在这里,我们报告了一种合成 3-氨基喹啉-2(1 H )-one 的替代方法,该方法通过级联 C-N 键形成和脱氮过程编辑分子骨架,克服了传统方法的局限性。我们使用 TMSN 3作为胺化剂,并使用多种 3-亚叉吲哚作为 quinolin-2(1 H )-one 主链的合成前体,这对敏感官能团具有显着的耐受性。对照实验表明三唑啉中间体在产物的形成中起重要作用。光谱研究进一步确定了潜在的反应途径。
Stereoselective Synthesis of Functionally Rich Spirooctahydroquinoline Oxindoles via Enynamide Cycloisomerisation/[4+2]‐Addition Sequence
作者:Madavi S. Prasad、Aman Kumar Jha、Sankar Bharani
DOI:10.1002/adsc.202400162
日期:2024.5.21
Creating an expedient method for synthesizing biologically significant functionally rich octahydroquinoline is a highly sought‐after yet challenging endeavour. In this report, we document an unprecedentedapproach to the construction of novel spirooctahydroquinoline oxindole architectures. The reaction proceeds through Pd (II) catalyzed cycloisomerisation and quinine catalyzed [4+2]‐addition sequence to afford
创建一种合成具有重要生物学意义、功能丰富的八氢喹啉的简便方法是一项备受追捧但具有挑战性的努力。在这份报告中,我们记录了一种前所未有的构建新型螺八氢喹啉羟吲哚结构的方法。该反应通过 Pd (II) 催化的环异构化和奎宁催化的 [4+2] 加成序列进行,以中等至优异的产率(高达 91%)以具有三个连续立体中心(包括一个螺中心)的单一非对映体形式提供所需的加合物。生成了大量的文库(35 个示例),反映了合成的多功能性和官能团/取代基的耐受性。此外,通过三步序列,该加合物以优异的收率和选择性(95%收率和> 99:1 dr)转化为具有五个连续立体中心的医学上重要的氟代十氢环氧乙醇喹啉螺吲哚支架,这表明了所开发方法的合成实用性。
Metal-Free Regioselective Oxa-Michael Approach to Access Spirooxindole-Fused Tetrahydrofuran/Tetrahydropyran through [3 + 2]/ [4 + 2] Spirocyclization of Methyleneindolinones with Haloalcohols
作者:Amol T. Savekar、Ramesh A. Gaikwad、Suresh B. Waghmode
DOI:10.1021/acs.joc.4c00659
日期:2024.7.5
An efficient one-pot metal-free, base-catalyzed method has been developed for the regioselective [3 + 2]/[4 + 2] annulation reactions of electrophilic methyleneindolinones with haloalcohols to furnish spirooxindole derivatives under mild reaction conditions. This reaction afforded the corresponding products with two contiguous stereocenters including a quaternary center in good to excellent yield (up
开发了一种高效的一锅法无金属碱催化方法,用于亲电子亚甲基二氢吲哚酮与卤代醇的区域选择性[3 + 2]/[4 + 2]环化反应,在温和的反应条件下提供螺吲哚衍生物。该反应以良好至优异的产率(高达 95%)提供具有两个连续立体中心(包括四元中心)的相应产物,具有中等至良好的非对映选择性(高达 12.5:1 dr )和完全区域选择性。