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Catalytic Asymmetric Synthesis of [2,3]‐Fused Indoline Heterocycles through Inverse‐Electron‐Demand Aza‐Diels–Alder Reaction of Indoles with Azoalkenes 下载免费PDF全文
Min‐Chao Tong Xuan Chen Jun Li Rong Huang Haiyan Tao Prof. Dr. Chun‐Jiang Wang 《Angewandte Chemie (International ed. in English)》2014,53(18):4680-4684
An unprecedented catalytic asymmetric inverse‐electron‐demand aza‐Diels–Alder reaction of indoles with in situ formed azoalkenes is reported. A diverse set of [2,3]‐fused indoline heterocycles were achieved in generally good yields (up to 97 %) with high regioselectivity and diastereoselectivity (>20:1 d.r.), and with excellent enantioselectivity (up to 99 % ee). 相似文献
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Catalytic Enantioselective Inverse Electron Demand Hetero‐Diels–Alder Reaction with Allylsilanes 下载免费PDF全文
Yuki Matsumura Takahiro Suzuki Prof. Dr. Akira Sakakura Prof. Dr. Kazuaki Ishihara 《Angewandte Chemie (International ed. in English)》2014,53(24):6131-6134
The first diastereo‐ and enantioselective inverse electron demand hetero‐Diels–Alder reaction of β,γ‐unsaturated α‐ketoesters with allylsilanes is described. Chiral copper(II) catalysts successfully activate the β,γ‐unsaturated α‐ketoesters and promote the reaction with allylsilanes with excellent enantioselectivities. This process represents a new entry to chiral oxanes. 相似文献
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M. Sc. Vincent Eschenbrenner‐Lux Dipl.‐Biol. Philipp Küchler Dr. Slava Ziegler Dr. Kamal Kumar Prof. Herbert Waldmann 《Angewandte Chemie (International ed. in English)》2014,53(8):2134-2137
The imino Diels–Alder reaction is an efficient method for the synthesis of aza‐heterocycles. While different stereo‐ and enantioselective inverse‐electron‐demand imino Diels–Alder (IEDIDA) reactions have been reported before, IEDIDA reactions including electron‐deficient dienes are unprecedented. The first enantioselective IEDIDA reaction between electron‐poor chromone dienes and cyclic imines, catalyzed by zinc/binol complexes is described. The novel reaction provides a facile entry to a natural product inspired collection of ring‐fused quinolizines including a potent modulator of mitosis. 相似文献
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Chang Min Chih‐Tsung Lin Prof. Dr. Daniel Seidel 《Angewandte Chemie (International ed. in English)》2015,54(22):6608-6612
A readily available chiral Brønsted acid was identified as an efficient catalyst for intramolecular Povarov reactions. Polycyclic amines containing three contiguous stereogenic centers were obtained with excellent stereocontrol in a single step from secondary anilines and aldehydes possessing a pendent dienophile. These transformations constitute the first examples of catalytic enantioselective intramolecular aza‐Diels–Alder reactions. 相似文献
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Catalytic Asymmetric Inverse‐Electron‐Demand Oxa‐Diels–Alder Reaction of In Situ Generated ortho‐Quinone Methides with 3‐Methyl‐2‐Vinylindoles 下载免费PDF全文
Jia‐Jia Zhao Si‐Bing Sun Sai‐Huan He Dr. Qiong Wu Prof. Dr. Feng Shi 《Angewandte Chemie (International ed. in English)》2015,54(18):5460-5464
The first catalytic asymmetric inverse‐electron‐demand (IED) oxa‐Diels–Alder reaction of ortho‐quinone methides, generated in situ from ortho‐hydroxybenzyl alcohols, has been established. By selecting 3‐methyl‐2‐vinylindoles as a class of competent dienophiles, this approach provides an efficient strategy to construct an enantioenriched chroman framework with three adjacent stereogenic centers in high yields and excellent stereoselectivities (up to 99 % yield, >95:5 d.r., 99.5:0.5 e.r.). The utilization of ortho‐hydroxybenzyl alcohols as precursors of dienes and 3‐methyl‐2‐vinylindoles as dienophiles, as well as the hydrogen‐bonding activation mode of the substrates met the challenges of a catalytic asymmetric IED oxa‐Diels–Alder reaction. 相似文献
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Dr. Mingsheng Xie Dr. Lili Lin Prof. Dr. Xiaoming Feng 《Chemical record (New York, N.Y.)》2017,17(12):1184-1202
In this review, the recent developments in catalytic asymmetric inverse‐electron‐demand hetero‐Diels−Alder reaction, which is recognized as one of the most powerful routes to construct highly functionalized and enantioenriched six‐membered heterocycles, are described. The article is organized on the basis of different kinds of electron‐deficient heterodienes, including α,β‐unsaturated ketones/aldehydes, o‐benzoquinones, α,β‐unsaturated imines, N‐aryl imines, o‐benzoqinone imides, and other aza‐olefins. 相似文献
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An organocatalyst formed from a binaphthyl‐substituted diamine and trifluoromethanesulfonic acid exhibited unprecedented levels of exo selectivity in the Diels–Alder reaction of α,β‐unsaturated aldehydes with cyclopentadiene. A novel axially chiral diamine was also designed as an organocatalyst for an asymmetric variant of this reaction, in which the desired cycloadducts were formed with high diastereo‐ and enantioselectivities. The highest diastereoselectivity observed was greater than 20:1 in favor of the exo cycloadduct in the asymmetric Diels–Alder reaction of crotonaldehyde with cyclopentadiene. 相似文献
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Trio Catalysis Merging Enamine,Brønsted Acid,and Metal Lewis Acid Catalysis: Asymmetric Three‐Component Aza‐Diels–Alder Reaction of Substituted Cinnamaldehydes,Cyclic Ketones,and Arylamines 下载免费PDF全文
Dr. Yongming Deng Siddhartha Kumar Prof. Kraig Wheeler Prof. Hong Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(21):7874-7880
A trio catalyst system, composed of arylamine, BINOL‐derived phosphoric acid, and Y(OTf)3, enables the combination of enamine catalysis with both hard metal Lewis acid catalysis and Brønsted acid catalysis for the first time. Using this catalyst system, a three‐component aza‐Diels–Alder reaction of substituted cinnamaldehyde, cyclic ketone, and arylamine is carried out with high chemo‐ and enantioselectivity, affording a series of optically active 1,4‐dihydropyridine (DHP) derivatives are obtained in 91–99 % ee and 59–84 % yield. DHPs bearing a chiral quaternary carbon center are also obtained with good enantioselectivity and moderate yield (three examples). Preliminary mechanistic investigations have also been conducted. 相似文献
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《化学:亚洲杂志》2017,12(17):2142-2159
Inverse‐electron‐demand Diels–Alder (iEDDA) reactions are an intriguing class of cycloaddition reactions that have attracted increasing attention for their application in bioorthogonal chemistry, the total synthesis of natural products, and materials science. In many cases, the application of the iEDDA reaction has been demonstrated as an innovative approach to achieve target structures. The theoretical aspects of this class of reactions are of particular interest for scientists as a means to understand the various factors, such as steric strain and electron density of the attached groups, that govern the reaction and thus to elucidate the reaction mechanism. This review aims to summarize both theoretical investigations and application‐driven research work on the iEDDA reaction. First, the historical aspects and the theoretical basis of the reaction, especially recent advances in time‐dependent density functional theory (TD‐DFT) calculations, as well as catalysis strategies will be highlighted and discussed. Second, the applications of this novel reaction in the context of materials science, bioorthogonal chemistry, and total synthesis of natural products will be elaborated with selected recent examples. The challenges and opportunities of the iEDDA reaction will be highlighted to give more insight into its potential applications in many other research areas. 相似文献
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The Asymmetric Hetero‐Diels–Alder Reaction in the Syntheses of Biologically Relevant Compounds 下载免费PDF全文
Vincent Eschenbrenner‐Lux Dr. Kamal Kumar Prof. Dr. Herbert Waldmann 《Angewandte Chemie (International ed. in English)》2014,53(42):11146-11157
The hetero‐Diels–Alder reaction is one of the most powerful transformations in the chemistry toolbox for the synthesis of aza‐ and oxa‐heterocycles embodying multiple stereogenic centers. However, as compared to other cycloadditions, in particular the dipolar cycloadditions and the Diels–Alder reaction, the hetero‐Diels–Alder reaction has been much less explored and exploited in organic synthesis. Nevertheless, this powerful transformation has opened up efficient and creative routes to biologically relevant small molecules and different natural products which contain six‐membered oxygen or nitrogen ring systems. Recent developments in this field, in particular in the establishment of enantioselectively catalyzed hetero‐Diels–Alder cycloadditions steered by a plethora of different catalysts and the application of the resulting small molecules in chemical biology and medicinal chemistry research, are highlighted in this Minireview. 相似文献
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Xin Yuan Dr. Shan‐Jun Zhang Dr. Wei Du Prof. Dr. Ying‐Chun Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(31):11048-11052
β‐Trifluoromethyl (CF3) enones were proved to act as good dienophiles in asymmetric normal‐electron‐demand Diels–Alder cycloadditions with 2,4‐dienals under trienamine catalysis with a chiral secondary amine. The sequential reductive amination transformations with benzylamine produced cis‐ and trans‐fused chiral trifluoromethylated octahydroisoquinolines in a diastereodivergent manner by using NaBH(OAc)3 and NaBH3CN as the reductants, respectively. Moreover, other types of activated alkenes that bear a CF3 group have also been successfully utilized to construct a diverse range of chiral cyclic frameworks in high stereoselectivity. 相似文献
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Yin Zhu Xiaohong Chen Mingsheng Xie Shunxi Dong Zhen Qiao Dr. Lili Lin Dr. Xiaohua Liu Prof. Dr. Xiaoming Feng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(39):11963-11968
Highly enantioselective Diels–Alder (DA) and inverse‐electron‐demand hetero‐Diels–Alder (HDA) reactions of β,γ‐unsaturated α‐ketoesters with cyclopentadiene catalyzed by chiral N,N′‐dioxide–Cu(OTf)2 (Tf=triflate) complexes have been developed. Quantitative conversion of β,γ‐unsaturated α‐ketoesters and excellent diastereoselectivities (up to 99:1) and enantioselectivities (up to >99 % ee) were observed for a broad range of substrates. Both aromatic and aliphatic β,γ‐unsaturated α‐ketoesters were found to be suitable substrates for the reactions. Moreover, the chemoselectivity of the DA and HDA adducts were improved by regulating the reaction temperature. Good to high chemoselectivity (up to 94 %) of the DA adducts were obtained at room temperature, and moderate chemoselectivity (up to 65 %) of the HDA adducts were achieved at low temperature. The reaction also featured mild reaction conditions, a simple procedure, and remarkably low catalyst loading (0.1–1.5 mol %). A strong positive nonlinear effect was observed. 相似文献
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《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(35):10709-10712
A highly efficient catalytic enantioselective intramolecular Povarov reaction was developed with primary anilines as 2‐azadiene precursors. A wide variety of angularly fused azacycles were obtained without column chromatography in high to excellent yields and with excellent diastereo‐ and enantioselectivity (d.r.>99:1 and up to e.r. 99:1). Furthermore, the catalyst loading could be lowered to 1 mol %, and the obtained azacycles could be used as key intermediates for further transformations to generate additional molecular diversity. 相似文献