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1.
Chiral trifluoromethyl alcohol groups were introduced at the hindered ortho positions of 9,10-diphenylanthracenes to investigate their effects on the physical properties and reactivity towards oxidative dearomatization. In such compact structures, the position in different quadrants and the preferred orientation of the −CH(OH)CF3 groups were determined by the relative and absolute configurations of each stereoisomer, respectively. As a consequence, the stereochemistry governs the organization of the H-bonded molecules in single crystals (homochiral dimers vs ribbon), whereas in chlorinated solvents, they all behave as discrete compounds. Concerning their reactivity, the stereospecific dearomative oxidation of these molecules leads to 9,10-bis-spiro-isobenzofuran-anthracenes, when using organic single-electron transfer oxidants. The chiroptical properties of the alcohols and the corresponding dearomatized products were compared and showed an important modulation of the intensity.  相似文献   

2.
Hydrodefluorination (HDF) is a very important fundamental transformation for conversion of the C−F bond into the C−H bond in organic synthesis. In the past decade, much progress has been achieved with HDF through the utility of low-valent metals, transition-metal complexes and main-group Lewis acids. Recently, novel methods have been introduced for this purpose through photo- and electrochemical pathways, which are of great significance, due to their considerable environmental and economical advantages. This Review highlights the HDF of fluorinated organic compounds (FOCs) through photo- and electrochemical strategies, along with mechanistic insights.  相似文献   

3.
Allylic alcohols represent an important and highly versatile class of chiral building blocks for organic synthesis. This Review summarizes the plethora of methods developed for the catalytic asymmetric synthesis of enantioenriched allylic alcohols. These include: dynamic kinetic resolution (DKR/DKAT), nucleophilic 1,2‐addition to carbonyl groups, allylic substitution, oxidation of C? H bonds, the addition of O nucleophiles to π systems, reduction of unsaturated carbonyl compounds, and an alternative route from enantioenriched propargylic alcohols. Furthermore, these catalytic asymmetric processes are exemplified by their applications in the syntheses of complex molecules such as natural products and potential therapeutic agents.  相似文献   

4.
The development of reactions that convert alcohols into important chemical compounds saves our fossil carbon resources as alcohols can be obtained from indigestible biomass such as lignocellulose. The conservation of our rare noble metals is of similar importance, and their replacement by abundantly available transition metals, such as Mn, Fe, or Co (base or nonprecious metals), in key technologies such as catalysis is a promising option. Herein, we report on the first base-metal-catalyzed synthesis of pyrroles from alcohols and amino alcohols. The most efficient catalysts are Mn complexes stabilized by PN5P ligands whereas related Fe and Co complexes are inactive. The reaction proceeds under mild conditions at catalyst loadings as low as 0.5 mol %, and has a broad scope and attractive functional-group tolerance. These findings may inspire others to use Mn catalysts to replace Ir or Ru complexes in challenging dehydrogenation reactions.  相似文献   

5.
A chiral dicationic palladium complex is found to be an efficient Lewis acid catalyst for the synthesis of α‐fluoromethyl‐substituted tertiary alcohols using a three‐component coupling reaction. The reaction transforms three simple and readily available components (terminal alkyne, arene, and fluoromethylpyruvate) to valuable chiral organofluorine compounds. This strategy is completely atom‐economical and results in perfect regioselectivities and high enantioselectivities of the corresponding tertiary allylic alcohols in good to excellent yields.  相似文献   

6.
电化学技术已经在有机合成得到广泛重视,本文简要概述了利用羰基和亚胺的电化学烯丙基化反应合成高烯丙醇和高烯丙胺的方法. 该方法已经得到了比较瞩目的进展,特别是在水相中的电化学烯丙基化反应,充分体现了绿色化学的特点。在提高电流效率和区域选择性,利用手性催化剂进行手性合成等方面还期待更多的关注和发展.  相似文献   

7.
吴军  HUDSON  Harry R. 《中国化学》2002,20(12):1598-1601
IntroductionOrganophosphoruscompoundsarewidelyusedasin secticides ,herbicidesandfungicides .Inviewofthepos sibleinfluenceoffluorinesubstitutiononthebiologicalactivityoforganophosphoruscompoundswehaveturnedourattentiontothestudyofthesynthesisandbiologica…  相似文献   

8.
绿色合成:一个逐步形成的学科前沿   总被引:60,自引:0,他引:60  
黄培强  高景星 《化学进展》1998,10(3):265-272
绿色合成是有机合成化学面向新世纪的学科前沿。本文探讨绿色合成的目标及实现这一目标的一些可能途径。  相似文献   

9.
电子转移光氧化反应与光敏化的单重态氧反应是光氧化反应的两个最重要的组成部分。电子转移光氧化是随着光诱导电子转移反应研究的广泛开展而得以迅速发展的。近年来,与光诱导电子转移反应有密切关联的过渡金属配合物的可见光催化反应也已成为研究热点。一些过渡金属配合物催化的电子转移光氧化反应也已出现。本文根据电子转移光氧化反应的不同机理,对这些反应进行分类,介绍了不同类型的电子转移敏化剂(包括氰基芳烃类光敏剂、鎓盐类阳离子光敏剂、过渡金属配合物类光敏剂以及有机染料类光敏剂)引发的电子转移光氧化反应,并讨论了各类电子转移光氧化反应中底物的各种活性中间体、反应中氧的活性形式、可能的反应途径以及在有机合成中的应用。  相似文献   

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12.
黄强  隆泉  郑保忠 《化学进展》2004,16(2):236-242
介绍了固相有机合成中的连接基团,特别是带有隔离单元的连接基团、无痕迹连接基团、安全拉手型连接基团和复合型连接基团的基本概念、发展近况以及它们的应用.  相似文献   

13.
绿色化学与有机合成及有机合成中的原子经济性   总被引:28,自引:0,他引:28  
陆熙炎 《化学进展》1998,10(2):123-130
本文概述了有机合成和绿色化学的关系, 并介绍了原子经济性的概念及其在有机合成中的重要性。对21 世纪的化学发展提出了希望。  相似文献   

14.
The copper‐catalyzed hetero‐allylic asymmetric alkylation (h‐AAA) of functionalized Grignard reagents that contain alkene or alkyne moieties has been achieved with excellent regio‐ and enantioselectivity. The corresponding alkylation products were further transformed into a variety of highly functionalized cyclic and bicyclic alcohols with excellent control over the chemo‐, regio‐, and stereoselectivity.  相似文献   

15.
The Morita–Baylis–Hillman (MBH) reaction is one of the most useful and efficient protocols for constructing new carbon–carbon bonds between an activated olefin and electrophiles in the presence of a tertiary amine/phosphine. Herein, we present the use of MBH alcohols, which are obtained from the reaction of nitrostyrenes with aldehydes, as well as acetates and amines derived thereof in several organocatalytic transformations. Densely functionalised MBH adducts can also be used to synthesise substituted heteroaromatic compounds, such as furan, pyrrole, pyrazole and imidazole derivatives.  相似文献   

16.
单羟基聚乙二醇(mPEG)与端羧基链转移剂S-十二烷基-S-′(α,α′-二甲基-α″-乙酸)三硫代碳酸酯[DDMAT(1)]经酯化反应制得大分子链转移剂[mPEG-DDMAT(2)];以2为链转移剂,用AIBN引发1H,1H,2H,2H-全氟癸基丙烯酸酯(FA)的可逆加成-断裂链转移聚合(RAFT),合成了嵌段间强烈不相容的亲水/亲氟双亲嵌段共聚物[mPEG-b-PFA(3a~3k)。3在溶液中的自组装行为研究结果表明,3 f在D2O中PFA聚集形成核,mPEG形成冠层;3 j在正丙醇中自组装得到伸直状的珍珠项链状聚集体。  相似文献   

17.
鲁卓群  张树永 《化学教育》2015,36(20):79-81
影响有机合成选择性和收率的因素主要包括反应机理、反应温度、立体效应、副反应等。由于缺乏相关数据和方法,一般很难对反应的影响因素(如溶剂和反应温度)进行理论预测,这使得合成路线的优化非常繁琐耗时。本论文基于反应的可能机理,在估算活化能的基础上,利用物理化学原理对温度的影响进行了讨论。结果表明,运用物理化学原理进行简单分析即可对有机合成路线的优化提供有益的理论指导。  相似文献   

18.
郑绍军  杨丹丹  刘静  朱瑞  王瑜  高玉华 《合成化学》2016,24(12):1102-1111
铜试剂催化的偶联反应是直接构建碳 碳键最有效的方法之一。本文综述了铜试剂催化的偶联反应构筑六种碳 碳键的方法;重点阐述了铜试剂催化构筑C(SP2)-C(SP2)的研究进展,含分子间偶联和分子内偶联。参考文献44篇。  相似文献   

19.
综述了固相、液相组合化学中以可溶性离子液体为载体的有机合成新概念及最新研究进展,并主要介绍了离子液体作为载体负载反应底物在有机合成中的一些应用,如有关的重要有机反应、组合化学、小分子库合成等。该方法具有上载率高、适用反应范围宽、分离纯化简便、结构检测容易和可回收重复使用等诸多优越性,这对于传统的固相、液相合成方法是一个重大的进步。  相似文献   

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