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A reusable CuSO4 · 5H2O/cationic 2,2′‐bipyridyl system catalyzed the homocoupling reaction of terminal alkynes in water using I2 as the additive in the presence or absence of tetrabutylammonium bromide, giving the 1,3‐diynes in good to high yields. After reaction, the residual aqueous solution could be reused several times. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Renaud Beaudegnies Alain De Mesmaeker Aurélie Mallinger Myriam Baalouch André Goetz 《Tetrahedron letters》2010,51(20):2741-3222
We report the design and the efficient synthesis of novel spirocyclopropyl cyclohexane-1,3-dione and -1,3,5-trione units to be incorporated into potent HPPD inhibitors. New routes involving original combinations of synthetic equivalents of α-cyclopropyl ketone-α-anion and α-cyclopropyl ester-β-cation are described. 相似文献
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Reverse Engineering of Conjugated Microporous Polymers: Defect Structures of Tetrakis(4‐ethynylphenyl)stannane Networks 下载免费PDF全文
M. Sc. Andrea C. Uptmoor M. Sc. Jan Freudenberg M. Sc. S. Thimon Schwäbel Dipl. Chem. Fabian Paulus Dr. Frank Rominger Dr. Felix Hinkel Prof. Uwe H. F. Bunz 《Angewandte Chemie (International ed. in English)》2015,54(49):14673-14676
Two different conjugated microporous polymers (CMPs) based on tetrakis(4‐ethynylphenyl)stannane as the repeating unit were synthesized and their BET surfaces and thermal properties were investigated. The first direct method to elucidate the molecular structure of the organic linkers between the tin centers by digestion of the CMP is described. Selective cleavage of the tin–carbon bonds with chloroacetic acid afforded the isolated bridging units and provided insight into the surprisingly varied chemical composition of these networks. 相似文献
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A novel and general carbon-nitrogen and carbon-carbon cross-coupling reaction between 3,4-dihydropyrimidine-2-thiones and copper(I) carboxylates were performed in the presence of palladium acetate. The copper(I) carboxylates act not only as desulfurative reagents but also as sources of carbon nucleophiles. A wide array of highly substituted and functionalized pyrimidines scaffolds were synthesized in good yields. 相似文献
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Symmetrical diynes were synthesized by ligand‐free copper‐catalyzed homocoupling reaction of 1,1‐dibromo‐1‐alkenes using a DBU/DMSO system at room temperature in good to excellent yields dot.?1. 相似文献
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Xin-Zhang Yu Wen-Long Wei Yu-Lan Niu Xing Li Ming Wang Wen-Chao Gao 《Molecules (Basel, Switzerland)》2022,27(19)
Symmetrical diaryl sulfides and diaryl disulfides have been efficiently and selectively constructed via the homocoupling of sodium arenesulfinates. The selectivity of products relied on the different reaction systems: symmetrical diaryl sulfides were predominately obtained under the Pd(OAc)2 catalysis, whereas symmetrical diaryl sulfides were exclusively yielded in the presence of the reductive Fe/HCl system. 相似文献
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The electroreduction of differently substituted aromatic and aliphatic thioesters (RCOSR′) led to regioselective reactions depending on the nature of the substituents. Thus, the cleavage between the carbonyl group and the SR′ group afforded α-diketones and the cleavage between the RCOS group and the alkyl R′ group afforded thiocarboxylic acids selectively. 相似文献
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The past decades have witnessed the emergence of low-dimensional carbon-based nanostructures owing to their unique properties and various subsequent applications. It is of fundamental importance to explore ways to achieve atomically precise fabrication of these interesting structures. The newly developed on-surface synthesis approach provides an efficient strategy for this challenging issue, demonstrating the potential of atomically precise preparation of low-dimensional nanostructures. Up to now, the formation of various surface nanostructures, especially carbon-based ones, such as graphene nanoribbons (GNRs), kinds of organic (organometallic) chains and films, have been achieved via on-surface synthesis strategy, in which in-depth understanding of the reaction mechanism has also been explored. This review article will provide a general overview on the formation of one-dimensional carbon-based nanostructures via on-surface synthesis method. In this review, only a part of the on-surface chemical reactions (specifically, C−X (X=Cl, Br, I) and C−H activation reactions) under ultra-high vacuum conditions will be covered. 相似文献