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Nickel‐Catalyzed Dimerization and Alkylarylation of 1,3‐Dienes with Alkyl Fluorides and Aryl Grignard Reagents 下载免费PDF全文
Dr. Takanori Iwasaki Xin Min Asuka Fukuoka Prof. Dr. Hitoshi Kuniyasu Prof. Dr. Nobuaki Kambe 《Angewandte Chemie (International ed. in English)》2016,55(18):5550-5554
In the presence of a nickel catalyst, 1,3‐butadiene undergoes selective dimerization and alkylarylation with alkyl fluorides and aryl Grignard reagents to give 1,6‐octadienes with alkyl and aryl groups at the 3‐ and 8‐positions, respectively, by the consecutive formation of three carbon–carbon bonds. The formation of an anionic nickel complex plays an important role in forming C?C bonds with alkyl fluorides. 相似文献
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Copper‐Catalyzed Heteroarylboration of 1,3‐Dienes with 3‐Bromopyridines: A cine Substitution 下载免费PDF全文
Kevin B. Smith Dr. Yuan Huang Prof. M. Kevin Brown 《Angewandte Chemie (International ed. in English)》2018,57(21):6146-6149
A method for the heteroarylboration of 1,3‐dienes is presented. The process involves an unusual cine substitution of 3‐bromopyridine derivatives to deliver highly functionalized heterocyclic products. Mechanistic studies are included that clarify the details of this unusual process. 相似文献
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《化学:亚洲杂志》2017,12(22):2884-2888
An efficient method for the synthesis of homopropargylboronates by copper‐catalyzed alkynylboration of alkenes with diboron reagents and bromoalkynes has been developed. The alkynylboration reaction features high selectivity and efficiency, mild reaction conditions, wide substrate scope, and functional‐group compatibility, and is a highly attractive complement to existing methods for the synthesis of homopropargylboronates. Both the boryl and alkynyl groups are good potential functional groups for the subsequent manipulations that provide access to a variety of important molecule structures. 相似文献
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Cover Picture: Nickel‐Catalyzed Dimerization and Alkylarylation of 1,3‐Dienes with Alkyl Fluorides and Aryl Grignard Reagents (Angew. Chem. Int. Ed. 18/2016) 下载免费PDF全文
Dr. Takanori Iwasaki Xin Min Asuka Fukuoka Prof. Dr. Hitoshi Kuniyasu Prof. Dr. Nobuaki Kambe 《Angewandte Chemie (International ed. in English)》2016,55(18):5349-5349
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Dr. Takanori Iwasaki Ryo Akimoto Prof. Dr. Hitoshi Kuniyasu Prof. Dr. Nobuaki Kambe 《化学:亚洲杂志》2016,11(20):2834-2837
Iron‐catalyzed cross‐coupling reaction of vinylic ethers with aryl Grignard reagents is described. The reaction proceeded at room temperature with catalytic amounts of an iron salt without the aid of costly ligands and additives. In this catalytic system, vinylic C?O bonds were preferentially cleaved over aromatic C?O bonds of aryl ethers or aryl sulfonates. 相似文献
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Kazuhiko Semba Masataka Shinomiya Prof. Dr. Tetsuaki Fujihara Prof. Dr. Jun Terao Prof. Dr. Yasushi Tsuji 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(22):7125-7132
The highly selective copper‐catalyzed hydroboration of allenes has been developed. Allylboranes and alkenylboranes were selectively prepared by the judicious choice of catalytic species (copper hydride and boryl copper). Furthermore, two types of alkenylboranes could be selectively synthesized by the choice of an appropriate ligand. Mechanistic studies confirmed that the protonation of a (Z)‐σ‐allyl copper species, which was isolated and structurally characterized by single‐crystal X‐ray diffraction, was a key step in these reactions. Besides allenes, this method is also applicable to the selective hydroboration of 1,3‐diene derivatives to afford allylboranes and homoallylboranes. 相似文献
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《Angewandte Chemie (International ed. in English)》2017,56(20):5536-5540
Heteroatom‐containing organic molecules are of particular interest to medicinal chemists and materials scientists. A strategy to reach these architectures via direct difunctionalization of abundant 1,3‐dienes is especially attractive. Herein, we describe the development of a regio‐ and diastereoselective 1,4‐aminothiolation of 1,3‐dienes with a sulfur diimide reagent, a copper catalyst, and alkyl Grignard reagents. This unique protocol provides remote nitrogen and sulfur functionalities with high levels of stereocontrol. The reaction proceeds via a tandem hetero‐Diels–Alder cycloaddition of N,N′‐bis(benzenesulfonyl)sulfur diimide with 1,3‐diene followed by copper‐catalyzed Grignard substitution. Mechanistic studies support a copper catalyzed formation of an unprecedented [10‐S‐4] sulfurane that reductively eliminates to afford a 3,6‐dihydrothiazine, which is selectively converted to 1,4‐aminothiols. 相似文献
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Copper‐Catalyzed Intermolecular Trifluoromethylazidation of Alkenes: Convenient Access to CF3‐Containing Alkyl Azides 下载免费PDF全文
Fei Wang Xiaoxu Qi Zhaoli Liang Dr. Pinhong Chen Prof. Dr. Guosheng Liu 《Angewandte Chemie (International ed. in English)》2014,53(7):1881-1886
A novel copper‐catalyzed intermolecular trifluoromethylazidation of alkenes has been developed under mild reaction conditions. A variety of CF3‐containing organoazides were directly synthesized from a wide range of olefins, including activated and unactivated alkenes, and the resulting products can be easily transformed into the corresponding CF3‐containing amine derivatives. 相似文献
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Enantioselective Copper‐Catalyzed Decarboxylative Propargylic Alkylation of Propargyl β‐Ketoesters with a Chiral Ketimine P,N,N‐Ligand 下载免费PDF全文
Fu‐Lin Zhu Yuan Zou De‐Yang Zhang Ya‐Hui Wang Xin‐Hu Hu Song Chen Prof. Dr. Jie Xu Prof. Dr. Xiang‐Ping Hu 《Angewandte Chemie (International ed. in English)》2014,53(5):1410-1414
The first enantioselective copper‐catalyzed decarboxylative propargylic alkylation has been developed. Treatment of propargyl β‐ketoesters with a catalyst, prepared in situ from [Cu(CH3CN)4BF4] and a newly developed chiral tridentate ketimine P,N,N‐ligand under mild reaction conditions, generates β‐ethynyl ketones in good yields and with high enantioselectivities without requiring the pregeneration of ketone enolates. This new process provides facile access to a range of chiral β‐ethynyl ketones in a highly enantioenriched form. 相似文献
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Wenbin Mao Weichao Xue Elisabeth Irran Martin Oestreich 《Angewandte Chemie (International ed. in English)》2019,58(31):10723-10726
A new application of silicon Grignard reagents in C(sp3)?Si bond formation is reported. With the aid of BF3?OEt2, these silicon nucleophiles add across alkenes activated by various azaaryl groups under copper catalysis. An enantioselective version employing benzoxazole‐activated alkenes as substrates and a CuI‐josiphos complex as catalyst has been developed, forming the C(sp3)?Si bond with good to high enantiomeric ratios (up to 97:3). The method expands the toolbox for “conjugate addition” type C(sp3)?Si bond formation. 相似文献
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Copper‐Catalyzed Borocarbonylative Coupling of Internal Alkynes with Unactivated Alkyl Halides: Modular Synthesis of Tetrasubstituted β‐Borylenones 下载免费PDF全文
Li‐Jie Cheng Neal P. Mankad 《Angewandte Chemie (International ed. in English)》2018,57(32):10328-10332
Reported is a general procedure to synthesize tetrasubstituted enones, which are borylated in the β‐position, using a copper‐catalyzed four‐component coupling reaction of simple chemical feedstocks: internal alkynes, alkyl halides, bis(pinacolato)diboron (B2pin2), and CO. A broad scope of highly functionalized β‐borylated enones, a largely unknown class of organic compounds, can be accessed efficiently using this method. The synthesis of all‐carbon tetrasubstituted enones was realized by employing the β‐borylated enone unit, without purification, in a Suzuki–Miyaura coupling. The utility of the method was further demonstrated by various transformations, including halogenation, oxidation, and protodeboration, of the corresponding reduced oxaborole species to provide densely substituted allylic alcohol and ketone products. 相似文献
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Laurine Gonnard Dr. Amandine Guérinot Prof. Janine Cossy 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(36):12797-12803
A cobalt‐catalyzed cross‐coupling between 3‐ and 4‐iodopiperidines and Grignard reagents is disclosed. The reaction is an efficient, cheap, chemoselective, and flexible way to functionalize piperidines. This coupling was used as the key step to realize a short synthesis of (±)‐preclamol. Some mechanistic investigations were conducted that highlight the formation of radical intermediates. 相似文献
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Copper‐Catalyzed Oxy‐Alkenylation of Homoallylic Alcohols to Generate Functional syn‐1,3‐Diol Derivatives 下载免费PDF全文
Dean Holt Prof. Matthew J. Gaunt 《Angewandte Chemie (International ed. in English)》2015,54(27):7857-7861
A novel method for the synthesis of a wide range of functionalized 1,3‐diol derivatives is reported. Employing a copper‐catalyzed oxy‐alkenylation strategy, a range of readily available, substituted homoallylic alcohol derivatives and alkenyl(aryl) iodonium salts combine to form syn‐1,3‐carbonates in excellent yield and with high selectivity. Furthermore, the products formed are amenable to an iterative reaction sequence, thus affording highly complex polyketide‐like fragments. 相似文献