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Heck反应作为构建C—C键最为强大和实用的合成工具之一,经过数十年的发展已逐渐趋于成熟,并在各种功能分子的合成中获得了极为广泛的应用.近年来,随着光催化的兴起,可见光诱导的钯催化Heck反应也随之快速发展起来.作为一种新颖的C—C键构建策略,可见光诱导的Heck反应极大地扩展了底物的适用范围,包括亲核试剂和亲电试剂.同时,这种由激发态钯络合物引发,机理上涉及杂化的自由基-PdⅠ物种的特殊反应路径也使得可见光诱导的钯催化Heck反应表现出条件温和、官能团兼容性好以及转化多样性等特点,是对经典Heck反应的极大补充,在功能分子的合成以及复杂化合物的后期修饰等方面极具应用潜力.根据反应亲核/亲电试剂种类,以及串联反应类型,对可见光诱导的Heck反应进行归类和总结,并对部分反应机理进行了简要阐述. 相似文献
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非钯催化剂催化Heck反应研究进展 总被引:1,自引:0,他引:1
非钯催化剂用于催化Heck反应有较多的报道.与钯催化剂相比,一些非钯催化剂(如镍、铜、钴等)显示了更优越的性能.近年来,铂、铑、钌、铁等催化体系也被用于Heck反应.对近年来非钯催化剂用于催化Heck反应的研究进行了归纳总结. 相似文献
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芳烃与烯烃通过两分子sp2-C—H键脱氢偶联,构建多取代烯烃的反应称之为氧化Heck反应或脱氢Heck反应,也叫Fujiwara-Moritani反应.在过去的几十年里,由于此类反应直接通过C—H键官能团化形成C—C键而备受关注.然而,绝大多数的此类转化只能适用于缺电子烯烃.富电子烯烃如烯丙酯或烯丙醚类化合物参与的氧化Heck偶联很少被报道.近几年来,我们课题组以及其他研究小组发展了一些十分高效的钯催化芳烃/烯烃与烯丙酯/烯丙醚的氧化脱氢偶联新方法.本文将概述这些有趣的、原子经济的氧化偶联反应的最新研究进展. 相似文献
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氟喹诺酮作为钯催化Heck反应有效配体的研究 总被引:3,自引:2,他引:1
研究了氟喹诺酮作为钯催化Heck反应的有效配体. 碘苯、溴苯和其它芳基卤衍生物与丙烯酸丁酯、苯乙烯等取代乙烯类化合物在钯和氟喹诺酮的催化下发生Heck反应. 讨论了配体、催化剂用量、碱和溶剂对Heck反应产率的影响. 该反应的最优化条件是: 钯源为Pd(OAc)2 (0.1 mol%), 诺氟沙星作为配体(0.2 mol%), K2CO3作为碱, DMA作为溶剂, 取代碘苯及溴苯和它们的衍生物与丙烯酸丁酯、苯乙烯等乙烯基化合物的反应均可以得到高收率的目标偶联产物. 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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Xuan Jiang Mao‐Mao Zhang Wei Xiong Liang‐Qiu Lu Wen‐Jing Xiao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(8):2424-2428
The palladium‐catalyzed Heck reaction is a well‐known, Nobel Prize winning transformation for producing alkenes. Unlike the alkenyl and aryl variants of the Heck reaction, the alkyl‐Heck reaction is still underdeveloped owing to the competitive side reactions of alkyl–palladium species. Herein, we describe the development of a deaminative alkyl‐Heck‐type reaction that proceeds through C?N bond activation by visible‐light photoredox catalysis. A variety of aliphatic primary amines were found to be efficient starting materials for this new process, affording the corresponding alkene products in good yields under mild reaction conditions. Moreover, this strategy was successfully applied to deaminative carbonylative alkyl‐Heck‐type reactions. 相似文献
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Xiaobang Gao 《Tetrahedron letters》2004,45(44):8169-8171
α-Halo vinyl ethers were successfully applied to palladium-catalyzed Heck reaction. Reactions of α-halo vinyl ether with alkenes under various Heck conditions form a new carbon-carbon bond along with a vinyl ether functionality, which can be further manipulated. This is the first synthetic methodology for the coupling of an acyl synthon with alkene employing Heck reaction. 相似文献
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A new synthetic protocol has been developed for the arylation of secondary and N-alkylated amide Heck precursors by the implementation of the palladium-catalyzed intramolecular Heck reaction strategies. 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 new method for the preparation of SBA-15-supported palladium catalyst for Heck reaction in supercritical carbon dioxide was presented.The newly formed SBA-15-supported palladium catalyst(Ph-SBA-15-PPh3-Pd) exhibited high catalytic activity for the Heck reaction of 4-nitrobromobenzene with methyl acrylate.The catalyst can be reused several times without a loss of activity. 相似文献
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<正>A ligand-free Heck reaction catalyzed by in situ-generated palladium nanoparticles in PEG-400 has been developed.This catalytic system is a simple and active protocol for the Heck reaction of aryl halides under mild conditions.Comparative experiments demonstrated that the Heck reaction catalyzed by the palladium nanoparticles in situ-generated under the Heck reaction conditions was carried out much quicker than that by the in ex situ-generated ones. 相似文献
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Phipps RJ McMurray L Ritter S Duong HA Gaunt MJ 《Journal of the American Chemical Society》2012,134(26):10773-10776
Alkenes and arenes represent two classes of feedstock compounds whose union has fundamental importance to synthetic organic chemistry. We report a new approach to alkene arylation using diaryliodonium salts and Cu catalysis. Using a range of simple alkenes, we have shown that the product outcomes differ significantly from those commonly obtained by the Heck reaction. We have used these insights to develop a number of new tandem and cascade reactions that transform readily available alkenes into complex arylated products that may have broad applications in chemical synthesis. 相似文献