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3位含有季碳手性中心的吲哚啉并环化合物是一类非常重要的化合物, 广泛存在于各种天然产物和具有生物活性的分子中. 化学家们发展了多种有效的途径来合成这类化合物. 其中以方便易得的吲哚衍生物为起始原料, 利用不对称去芳构化\环化串联的方法最为简单高效, 但多数工作都是从色胺或色醇衍生物出发, 合成二氢吡咯并吲哚啉或二氢呋喃并吲哚啉化合物. 因此, 发展其他类型的吲哚衍生物的不对称去芳构化\环化反应显得非常有必要. 作者课题组发展了手性磷酸催化的吲哚衍生物与甲基乙烯基酮的不对称Michael加成\环化串联反应. 以5 mol% (R)-SPINOL为骨架的手性磷酸(R)-4c为催化剂, 以中等到良好的收率和优秀的对映选择性构建了一系列手性吲哚[2,3-b]并氢化喹啉化合物, 而且该催化体系对于克级规模反应同样能够获得很好的结果. 相似文献
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A Kinetic Dearomatization Strategy for an Expedient Biomimetic Route to the Bielschowskysin Skeleton 下载免费PDF全文
Paul Scesa Medhi Wangpaichitr Niramol Savaraj Dr. Lyndon West Dr. Stéphane P. Roche 《Angewandte Chemie (International ed. in English)》2018,57(5):1316-1321
Bielschowskysin ( 1 ), the flagship of the furanocembranoid diterpene family, has attracted attention from chemists owing to its intriguing and daunting polycyclic architecture and medicinal potential against lung cancer. The high level of functionalization of 1 poses a considerable challenge to synthesis. Herein, a stereoselective furan dearomatization strategy of furanocembranoids was achieved via the intermediacy of chlorohydrins. The stereochemical course of the kinetic dearomatization was established, and the C3 configuration of the resulting exo‐enol ether intermediates proved to be essential to complete the late‐stage transannular [2+2] photocycloaddition. Overall, this biomimetic strategy starting from the natural product acerosolide ( 9 ) featured an unprecedented regio‐ and highly stereoselective furan dearomatization, which provided rapid access to the pivotal exo‐enol ethers en route to the intricate bielschowskyane skeleton. 相似文献
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Wen Shao He Li Chuan Liu Prof. Dr. Chen‐Jiang Liu Prof. Dr. Shu‐Li You 《Angewandte Chemie (International ed. in English)》2015,54(26):7684-7687
The first copper‐catalyzed intermolecular dearomatization of indoles by an asymmetric propargylic substitution reaction was developed. This method provides a highly efficient synthesis of versatile furoindoline and pyrroloindoline derivatives containing a quaternary carbon stereogenic center and a terminal alkyne moiety with up to 86 % yield and 98 % ee. 相似文献
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Guang‐Jian Mei Xiwen Tang Yildiz Tasdan Yixin Lu 《Angewandte Chemie (International ed. in English)》2020,59(2):648-652
The enantioselective dearomatization of indoles by an organocatalytic (3+2) reaction has been established. The reaction makes use of simple indole derivatives as substrates, and employs azoalkenes reaction partners. A wide range of pyrroloindolines containing an all‐carbon quaternary stereogenic center were readily prepared in high yields and with excellent enantioselectivities. 相似文献
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Dr. Luciano Cuesta Dr. Tatiana Soler Dr. Esteban P. Urriolabeitia 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(47):15178-15189
Novel cycloruthenated complexes 2 a – c , 4 a – c , and 6 a, b based on heteroaromatic cores have been synthesized by reaction of a series of heterocycle‐based imines with [{RuCl(η6‐p‐cymene)}2(μ? Cl)2] and Cu(OAc)2. This approach has proved efficient for the cyclometalation of thiophene, benzothiophene, furan, benzofuran, pyrrole, and indole derivatives. In addition, even a double cyclometalation process over the same heterocyclic ring is possible, yielding unprecedented bimetallic complexes. These ruthenacycles react with 3‐hexyne through an unexpected pathway, which involves the coupling of the original imino heterocycle and acetylene followed by dearomatization to afford fused hetero‐hydropyridyl ligands bonded to the {Ru(p‐cymene)} organometallic moiety (i.e., 7 a – c and 8 a – c ). These complexes represent, as far as we know, the first examples of this type of compound within the context of cyclometalation, and an exhaustive analysis of their structure was carried out in solution and solid state. Furthermore, these unique species react with CuCl2, which promotes the rearomatization and the release of highly valuable aromatic fused bis‐heterocycles (i.e., 9 a – c , 10 a – c, 11 a , and 12 a/12 a′ ), providing a novel and appealing synthetic route to this extraordinary family of molecules. 相似文献
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Palladium(0)‐Catalyzed Intermolecular Allylic Dearomatization of Indoles by a Formal [4+2] Cycloaddition Reaction 下载免费PDF全文
Run‐Duo Gao Qing‐Long Xu Bo Zhang Yiting Gu Prof. Li‐Xin Dai Prof. Dr. Shu‐Li You 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(33):11601-11604
Bridged indoline derivatives were synthesized by an intermolecular Pd‐catalyzed allylic dearomatization reaction of substituted indoles. The reaction between indoles and allyl carbonates bearing a nucleophilic alcohol side‐chain proceeds in a cascade fashion, providing bridged indolines in excellent enantioselectivity. 相似文献
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Edon Vitaku David T. Smith Prof. Dr. Jon T. Njardarson 《Angewandte Chemie (International ed. in English)》2016,55(6):2243-2247
Nitrogen heterocycles are found in a majority of approved small‐molecule pharmaceuticals, and the number of approved fluorinated drugs is increasing each decade. Therefore, new approaches for accessing fluorinated nitrogen heterocycles are of great significance. A novel, scalable, and metal‐free method for accessing a wide range of fluorinated indoles is described. This oxidative‐dearomatization‐enabled approach assembles 2‐trifluoromethyl NH‐indole products from simple commercially available anilines with hexafluoroacetylacetone in the presence of an organic oxidant. The nature of the aniline N‐capping group is critical for the success of this new reaction. Furthermore, the indole products contain a 3‐trifluoroacetyl group, which can be exploited to access a plethora of useful functional groups. 相似文献
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A bicyclo[2.2.2]octane C/D ring system,with a lactonic ring at C-8 and C-9,of the atisine-type C20-diterpenoid alkaloids,was successfully synthesized,using an oxidative dearomatization/intramolecular Diels-Alder reaction. 相似文献
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Stereoselective route to tricyclo[5.3.1.01,5]undecane and bicyclo[4.2.0]octane ring systems present in the molecular structure of tricycloillicinone, cedrenoids and endiandric acid, elysiapyrones, respectively, is described. A tandem oxidative dearomatization of o-hydroxymethylphenol, π4s+π2s cycloaddition, reactivity modulation in excited state and ring-closing metathesis are the key features of our approach. 相似文献