共查询到20条相似文献,搜索用时 31 毫秒
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吲哚以其独特的化学结构使其衍生出的化合物都具有独特的生理活性,它们在医药、农药、香料、色氨酸等领域发挥着重要的作用,是一类非常重要的杂环类精细化工中间体。因此,长久以来发展简单、通用,特别是具有区域选择性的方法合成吲哚类化合物一直吸引了人们的研究兴趣[1]。在已经发展起来的合成吲哚类化合物的许多方法中,Heck反应[2],即Pd催化卤代物与烯烃构筑碳碳键的方法,由于其温和的反应条件和广泛的官能团相容性,已经成为合成吲哚及其衍生物采用最多的方法[3]。早在1984年,Suzuki[4]就报道合成了化合物3-乙氧羰基-2-甲基吲哚,其是由… 相似文献
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综述了不对称Heck反应在天然产物合成中的应用,按照分子内和分子间的不对称Heck反应分两个方面加以介绍和总结。参考文献26篇。 相似文献
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钯催化的交叉偶联反应是非常实用的合成新方法.文章给出了Heck反应、Negishi反应和Suzuki反应的概念,对其反应机理作了详细的说明,并对其在复杂化合物和天然产物全合成中的应用作了评价. 相似文献
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The palladium-catalyzed arylation of olefins (the Heck reaction) is one of the most versatile tools for C-C bond formation in organic synthesis. Phosphine ligands are generally used to stabilize the reactive palladium intermediates, the air-sensitivity of phosphine ligands, however, places significant limits on their synthetic applications. Recently, Yang1 and we2 have reported Heck and Suzuki reactions of highly active arenediazonium salts and halides catalyzed by air-stable monothiourea-Pd… 相似文献
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A practical and an efficient synthesis of three building blocks of tetrahydroisoquinoline alkaloid Ecteinascidin-743 was accomplished, starting from readily available piperonal, 2-methyl anisole, and veratraldehyde. A combination of Vilsmeier-Haack reaction and Sharpless asymmetric dihydroxylation was employed for the synthesis of building blocks A and B whereas a Heck reaction in PEG-2000 and aza-Michael reactions were employed for the synthesis of building block C. 相似文献
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Kalesse M Chary KP Quitschalle M Burzlaff A Kasper C Scheper T 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(5):1129-1136
Callystatin A is a prominent member of a class of natural products which display promising growth inhibition of cancer cells in their biological profile. The challenging structure and the interesting biological activity of (-)-callystatin A fueled our interest in the synthesis of this marine natural product. We achieved the total synthesis using a highly convergent approach joining four subunits together with a Wittig olefination, a selective Heck reaction and an aldol reaction as the pivotal steps. The aldol reaction as one of the final transformations during the synthesis opens fast access to a variety of structural analogues and circumvents tedious protecting group manipulations. Here we report an improved synthesis utilizing a modified vinyl iodide which shortens the synthesis by two steps. Additionally, first biological results will be reported. 相似文献
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Sabrina M. Nobre Mauro N. Muniz Marcus Seferin Wagner M. da Silva Adriano L. Monteiro 《应用有机金属化学》2011,25(4):289-293
We have developed a sequential and selective Pd‐catalyzed double‐Heck arylation of ethylene that results in non‐symmetrical nitro‐stilbene analogs of trans‐resveratrol at excellent yields. A catalytic system consisting of Pd(OAc)2 and P(o‐tolyl)3 permitted us to carry out the two consecutive Heck arylations without losing activity from the first to the second Heck reaction. After the first Heck arylation of ethylene, no isolation or additional catalyst loading is required for the second Heck arylation reaction. This protocol was applied to the synthesis of methylated trans‐resveratrol, which was obtained at a 65% overall yield. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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A new stereoselective approach for the synthesis of AI-77-B has been described. Dihydroisocoumarin fragment was made in two routes using Heck reaction followed by oxidation of the olefin and LDA mediated reaction. The chiral amino acid moiety has been obtained from d-ribose involving Grignard reaction on ribosylimine. Finally, condensation of dihydroisocoumarin with acid fragment furnished the title target AI-77-B. 相似文献
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Subhash P. Chavan Dushant A. Khobragade Ashok B. Pathak Uttam R. Kalkote 《合成通讯》2013,43(18):3143-3149
A formal total synthesis of antidepressant (±)‐paroxetine employing a solvent‐free Heck reaction is disclosed. 相似文献
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Bruno R.V. Ferreira 《Tetrahedron》2009,65(36):7712-9297
An improved and highly efficient synthesis of several α-benzyl-β-ketoesters from Morita-Baylis-Hillman adducts is described. These adducts were used as substrates for an intermolecular Heck reaction catalyzed by a Nájera oxime-derived palladacycles. These efficient catalytic conditions probed to be very selective providing only the corresponding functionalized β-ketoesters in high yield with no decarboxylation product. It seems that the method herein described is one of the most efficient for the synthesis of α-benzyl-β-ketoesters. 相似文献
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The synthesis of highly substituted dibenzo-azocine systems is still lacking. An efficient synthetic protocol utilizing the sequential aromatic aza-Claisen rearrangement followed by the implementation of the intramolecular Heck reaction as a key step has been developed for the synthesis of various dibenzo-azocine derivatives of biological relevance. 相似文献
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Yoichi M.A Yamada 《Tetrahedron》2004,60(18):4097-4105
The efficient heterogeneous Heck reaction was achieved by a new networked and supramolecular catalyst PdAS-V (1b). Employing of PdAS-V in 5.0×10−5 mol equiv. efficiently progressed the heterogeneous Heck reaction of a series of aryl iodides with acrylates, styrenes and acrylic acid. PdAS-V was successfully recycled five times without any decrease in its activity, and showed good stability in toluene and water, and hence the Heck reaction was efficiently performed in both reaction media. The use of 8.0×10−7 mol equiv. of PdAS-V resulted in the coupling product in 92% yield with the turnover number (TON) and the turnover frequency (TOF) of PdAS-V reached up to 1,150,000 and 12,000, respectively. The efficient synthesis of resveratrol was achieved via the PdAS-V-promoted Heck reaction. 相似文献
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The synthesis and desymmetrisation of bicyclo[4.4.0]decadienes is described; the enantioselective Heck reaction using JOSIPHOS as a planar-chiral complex produces a tetracyclic system with three stereogenic centers in up to 84% enantiomeric purity. 相似文献
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The enantioselective formal synthesis of (?)-aurantioclavine is described. The core tricyclic skeleton was synthesized using a Pd-catalyzed Heck insertion–allylic amination cascade. The stereocenter was constructed by a highly enantioselective organocatalytic asymmetric aziridination reaction. 相似文献
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A palladium catalyzed domino intermolecular Suzuki followed by intramolecular Heck coupling is described. This strategy afforded a novel and convenient synthesis of various 9-fluorenylidene derivatives in one-pot under relatively mild reaction condition. 相似文献
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Tayebeh Besharati-Seidani Ali Keivanloo Babak Kaboudin Akihiro Yoshida Tsutomu Yokomatsu 《Tetrahedron》2018,74(19):2350-2358
The regioselective synthesis of 1-alkyl-2-aryl-3-acyl pyrrolo[2,3-b]quinoxalines through palladium-catalyzed Heck coupling reaction/heteroannulation was reported. The reaction of N-alkyl/benzyl-3-chloroquinoxaline-2-amines with chalcones catalyzed by Pd(OAc)2 in the presence of KOtBu, as the base, in DMSO afforded the desired products in good-to-high yields. The MIC and MBC determinations revealed that these compounds could be used in the future research works for the development of antibiotics. 相似文献