铟试剂在有机合成中的应用

综述了近十年来铟试剂在有机合成中的应用。重点讨论了铟试剂参与的有关碳-碳键形成的反应,如羰基化合物的烯丙基化、Reformatsky反应、成环以及三氯化铟作为Lewis酸的催化反应以及铟试剂的水相反应化学。铟试剂的这些反应,尤其是水相反应具有其它金属有机试剂在化学选择性和立体选择性方面具有独特的优势。     

三价铟化合物在有机合成中的应用

综述了近年来三价铟化合物促进的多种有机反应及其在有机合成中的应用,其中重点讨论了三价铟化合物促进下的碳-碳键和碳-杂原子键的形成反应.     

塞曼火焰原子吸收光谱法直接测定金属铟及铟合金中微量铅

对于纯铟及铟合金中微量铅的测定,通常采用在氢溴酸介质中,用甲基异丁基酮萃取,分离主体铟及其他干扰元素,水相于塞曼火焰原子吸收光谱仪波长283.3nm处测定铅的吸光度。方法操作流程长,经过两次萃取,易引入误差,不适合大批量的检测,而且所用的有机试剂易污染环境。鉴于以上弊端,本文介绍了利用塞曼火焰原子吸收光谱仪灵敏度高,选择性好,扣背景能力强等特点,在不用分离主体铟的情况下于5%(体积分数)盐酸介质中直接测定微量铅的方法。本法操作简单、迅速,且稳定性好,结果准确可靠,提高了分析速度。1　试验部分1.1　仪器与试剂GGX 6A塞曼…     

各种金属参与的水相Barbier-Type反应

详细地概括了各种金属和金属盐参与的水相Barbier-Type反应,对反应机理以及反应的化学、区域和立体选择性进行了系统的总结,此外,还对水相Barbier-Type反应在有机合成中的应用作了初步的介绍.     

芳基碘鎓盐促进芳基化反应的应用

二芳基碘鎓盐属于有机高价碘化合物,具有无毒、反应条件温和以及良好的选择性等优点,在有机合成中具有重要地位,受到广大化学工作者的关注。近年来,利用二芳基碘鎓盐在金属催化下进行的芳基化反应为一些难以合成的杂环化合物的合成提供了简便、高效的方法;同时,二芳基碘鎓盐在无催化剂下进行的芳基化反应,为C—C偶联反应开辟了新的绿色合成路线。本文综述了近年来二芳基碘鎓盐在有机合成中促进芳基化反应的最新进展,着重介绍了利用二芳基碘鎓盐作为芳基化试剂与有机金属试剂、烯烃和炔烃类以及杂环化合物进行芳基化反应的研究;总结了二芳基碘鎓盐与杂环化合物反应中钯催化和铜催化下芳基化反应的机理,最后对二芳基碘鎓盐在今后有机合成中的应用作出了展望。     

有机硅试剂参与过渡金属催化的C-H官能团化反应形成C-C键的研究进展

作为一类重要的有机金属试剂,有机硅试剂在有机合成化学的C—C键形成中得到了广泛应用.综述了近年来有机硅试剂参与的过渡金属催化下C—H官能团化反应形成C—C键的研究进展,重点介绍了Pd催化下C—H官能团化的Hiyama偶联反应.     

金属参与的水相烯丙基化反应*

近30年来,水介质中碳-碳键的形成一直是研究的热点,其优越性也逐渐被人们所认知。在已发现的水相金属有机反应中,水相烯丙基化反应是研究得较多和较深入的反应之一。水相烯丙基化反应由于其发展速度较快,新的金属及金属体系参与的烯丙基化反应以及水相烯丙基化反应的机理研究不断被报道。本文综述了水相中金属参与烯丙基化反应的最新研究进展,并对新的反应机理作了简要的阐述。     

水相金属有机化学

本文对近年来锡、锌、铋等介入下的水相金属有机化学作了综述。特别对水相Barbier 反应作了较详细的介绍, 同时也描述了一些典型的水相金属有机反应,如Immonium 阳离子的烷基化反应, α, β 不饱和化合物的共轭加成, 醇醛缩合反应及水溶性金属有机化合物的反应等。某些反应的机理也被讨论。     

2-碘酰基苯甲酸在有机合成中的研究与应用

高价有机碘化合物的反应性质与过渡金属相似,其参与的反应具有反应条件较温和、选择性好、产率高及环境友好等优点,因而近年来关于高价有机碘试剂的研究受到广泛关注,在有机合成领域中获得了较多应用.综述了近年来高价有机碘试剂2-碘酰基苯基酸(IBX)在有机合成中的研究及应用,包括IBX在氧化羟基、含氮化合物和含硫化合物,在制备αβ-不饱和羰基化合物和α,β-不饱和酯,以及在不对称合成等方面的应用.最后介绍了近期对IBX的改进.     

在水介质中进行的Barbier-Grignard反应

综述了铟、锌、锡等金属(试剂)诱导的,在水介质中进行的Barbier-Grignard反应,并讨论了该反应的化学选择性、区域选择性和立体选择性。     

Access to Nitriles from Aldehydes Mediated by an Oxoammonium Salt

A scalable, high yielding, rapid route to access an array of nitriles from aldehydes mediated by an oxoammonium salt (4‐acetylamino‐2,2,6,6‐tetramethylpiperidine‐1‐oxoammonium tetrafluoroborate) and hexamethyldisilazane (HMDS) as an ammonia surrogate has been developed. The reaction likely involves two distinct chemical transformations: reversible silyl‐imine formation between HMDS and an aldehyde, followed by oxidation mediated by the oxoammonium salt and desilylation to furnish a nitrile. The spent oxidant can be easily recovered and used to regenerate the oxoammonium salt oxidant.     

Structural transformations in macromolecules of synthetic nonionogenic polymers and DNA in salt-containing aqueous solutions

The influence of salt additives on structural transformations in macromolecules of synthetic polymers free of ionogenic groups and DNA molecules has been determined with the use of the nanosecond dynamics luminescent method. When polyvalent metal salts are added, a coil-globule transition is observed in macromolecules of poly(N-n-propylmethacrylamide), while structural transformations occur in DNA macromolecules in aqueous solutions, processes that are accompanied by the passage of low-molecular-mass organic cations intercalated into DNA into solution. These transformations make themselves evident when polyvalent metal ions are added in an amount of one Mt³⁺ ion per ten phosphate groups of DNA. The same effect takes place when salts of polycations are added to solutions of DNA-polycation interpolyelectrolyte complexes.     

镍N-杂环卡宾配合物在均相催化偶联反应中的应用

 近十几年来, N-杂环卡宾的配位化学和金属有机化学发展迅速, 已成为均相催化反应中研究最为广泛的配体之一. 在许多过渡金属催化的有机合成反应中特别是偶联反应中, N-杂环卡宾与传统有机膦配体相比具有较高的反应性. 镍价格低廉, 在很多反应中有望替代贵金属钯催化剂. 本文总结了镍 N-杂环卡宾化合物在催化交叉偶联反应和还原偶联反应中的最新应用进展.     

Dual Catalysis Sees the Light: Combining Photoredox with Organo‐, Acid,and Transition‐Metal Catalysis

The photoredox activation of organic substrates with visible light is a powerful methodology that generates reactive radical species under very mild conditions. When combined with another catalytic process in a dual catalytic system, novel, visible‐light‐promoted transformations have been realized that do not proceed using either catalyst in isolation. In this minireview, the state of the art in organic reactions mediated by dual catalytic systems merging photoredox activation with organo‐, acid or metal catalysis is discussed.     

Carbocatalysis in Liquid‐Phase Reactions

There is broad interest in metal‐free catalysis for sustainable chemistry. Carbocatalysis is a “green” option for catalytic transformations in the gas phase as well as in the liquid phase. This is evident by the numerous reports on gas‐phase dehydrogenation and selective oxidation where carbon can be used as a successful alternative to metal oxide systems. Carbocatalysis for liquid‐phase reactions, especially for organic synthesis, is an emerging research discipline and has undergone rapid development in recent years. This Review provides a critical analysis on the state‐of‐the‐art of carbocatalysts for liquid‐phase reactions, with a focus on the underlying mechanisms as well as the advantages and limitations of metal‐free carbocatalysts.     

Difunctionalization of Alkenes Involving Metal Migration

The direct difunctionalization of alkenes, a cheap and abundant feedstock, represents one of the most attractive strategies for increasing molecular complexity in synthetic organic chemistry. In contrast with the 1,2‐difunctionalization of alkenes, recent advances showcase alkene 1,n‐difunctionalizations (n≠2) involving metal migration is an emerging and rapidly growing area of research. This promising strategy not only opens a novel avenue for future development of alkene transformations, but also significantly expands upon the bond disconnections available in modern organic synthesis. This Minireview summarizes recent progress in the migratory difunctionalization of alkenes, with an emphasis on the driving force for metal migration.     

电子转移光氧化反应在有机合成中的应用

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。     

Liquid-liquid extraction with long-chain quaternary Ammonium Halides

The extraction of anionic chloro-complexes of certain metal ions using various long-chain quaternary ammonium halides in toluene and chloroform is described. The investigation has concerned itself mainly with coualt(II) and iron(III); a few extractions have also been carried out with indium(III) and gallium(in). The ion association of chloro-anionic complexes of iron, cobalt, indium and gallium in aqueous chloride media (hydrochloric acid or lithium chloride) with the quaternary ammonium ion in the organic phase is responsible for the extraction of the metal ion into the organic phase. Tlic extraction efficiency varies with the nature of the metal ion system involved as well as with the distribution of the quaternary compound and the size, shape and nature of the organic groups substituted in the quaternary compound.     

Two birds with one metallic stone: single-pot catalysis of fundamentally different transformations

Advances in metal catalysis have revolutionized organic synthesis, with the scope of metal-catalyzed reactions now covering nearly all areas of carbon-carbon, carbon-hydrogen, and carbon-heteroatom bond formation. For years, the goal was to develop catalysts that were highly selective for a single transformation. However, a promising current area of research is the use of a single catalyst to mediate more than one transformation in a selective manner. Whereas much early work was focused on using a catalyst for several similar transformations, recent investigations have shown that it is also possible to employ a single catalyst for several very different transformations in a single reaction sequence. This Minireview focuses on methods in which the mechanisms of the transformations are fundamentally very different.