Copper-mediated addition and substitution reactions of extended multiple bond systems
Copper-mediated addition and substitution reactions of extended multiple bond systems
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DOI：
10.1002/3527600086.ch4
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发表时间：
2002-01-01
期刊：
影响因子：
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通讯作者：
Hoffmann-Röder, A
中科院分区：
文献类型：
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作者：
Krause, N;Hoffmann-Röder, A
自从Gilman等人对有机铜化合物RCu[1]和二有机铜锂化合物R2CuLi[2]进行了首次研究以来，后者(直到今天仍被称为Gilman试剂)在用于形成碳-碳键的有机金属试剂中得到了广泛的应用。特别是，House等人的开创性工作。和Corey等人。使有机铜酸盐不仅成为许多饱和(卤代烷、酸性氯化物、环氧乙烷)和不饱和(烯丙基和丙烯酸衍生物)亲电试剂的替代反应的选择试剂，而且还用于α的1，4-加成反应，/-不饱和羰基化合物的1，4-加成反应，以及最后但并非最不重要的，非活性炔烃的碳铜反应[3]。在这些过程中，有机铜酸盐独特的反应性依赖于“软”亲核铜和“硬”亲电锂离子的相互作用，通过试剂的“微调”提供对反应性和选择性的控制。在过去的几十年里，有机铜化学在各个领域取得的巨大成就大部分都在这本书中得到了强调。这些内容包括阐明有机铜化合物的结构[4]及其转化机理[5](第二章)。1和10)，铜介导和铜催化的新工艺[6](Chapts.2、3和5)，非对映选择性反应(第二章6)，以及高对映选择性的取代反应和共轭加成反应[7]。7和8)。在这些领域中达到的高标准在全合成中铜促进的转化的许多应用中都有记载(第一章)。就底物而言，尽管简单的不饱和底物通常的1，4-加成和1，3-取代(SN20)反应到目前为止占主导地位，但具有扩展的多键系统(即具有两个或更多反应位置)的两元底物的类似转化直到最近才开始引起注意。在这里，系统的研究表明，这种1，5-取代，甚至1，6-和1，8-加成反应具有很高的区域选择性和立体选择性，特别是当底物除了一个或多个共轭双键外，还含有至少一个三键。这些不寻常的反应类型
Since the pioneering work of Gilman et al., who carried out the first investigations into organocopper compounds RCu [1] and lithium diorganocuprates R2CuLi [2], the latter reagents (still referred to even today as Gilman reagents) have been becoming widespread among organometallic reagents used for carbon-carbon bond formation. In particular, the seminal work of House et al. and Corey et al. has served to establish organocuprates as the reagents of choice not only for substitution reactions of many saturated (haloalkanes, acid chlorides, oxiranes) and unsaturated (allylic and propargylic derivatives) electrophiles, but also for 1, 4-addition reactions to α,/-unsaturated carbonyl compounds and, last but not least, for carbocuprations of non-activated alkynes [3]. In these processes, the unique reactivity of organocuprates relies on the interplay of the ‘‘soft’’, nucleophilic copper and the ‘‘hard’’, electrophilic lithium ion, offering control over reactivity and selectivity through ‘‘fine-tuning’’of the reagent. Most of the tremendous achievements in various fields of organocopper chemistry over the last few decades are highlighted in this book. These include the elucidation of the structures of organocopper compounds [4] and the mechanism of their transformations [5](Chapts. 1 and 10), new copper-mediated and copper-catalyzed processes [6](Chapts. 2, 3, and 5), diastereoselective reactions (Chapt. 6), and highly enantioselective substitution and conjugate addition reactions [7](Chapts. 7 and 8). The high standards attained in these fields are documented in numerous applications of copper-promoted transformations in total synthesis (Chapt. 9).As far as substrates are concerned, while the usual 1, 4-addition and 1, 3-substitution (SN20) reactions of simple unsaturated substrates have so far predominated, analogous transformations of ambident substrates with extended multiple bond systems (ie, with two or more reactive positions) have come to attention only recently. Here, systematic investigations have shown that such 1, 5-substitutions and even 1, 6-and 1, 8-addition reactions proceed highly regioselectively and stereoselectively, in particular when the substrate contains at least one triple bond besides one or more conjugated double bonds. These unusual reaction types not