Oxygen‐ and nitrogen‐assisted lithiation and carbolithiation of non‐aromatic compounds; properties of non‐aromatic organolithium compounds capable of intramolecular coordination to oxygen and nitrogen
Oxygen‐ and nitrogen‐assisted lithiation and carbolithiation of non‐aromatic compounds; properties of non‐aromatic organolithium compounds capable of intramolecular coordination to oxygen and nitrogen
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非芳香族化合物的氧和氮辅助锂化和碳锂化；能够与氧和氮进行分子内配位的非芳香族有机锂化合物的性质；
DOI：
10.1002/recl.19861050102
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发表时间：
1986
期刊：
影响因子：
--
通讯作者：
G. W. Klumpp
中科院分区：
文献类型：
--
作者：
G. W. Klumpp
这种新的方法学(“Neue Ar~MatenChemie”)是对传统的多取代芳香族化合物(主要是间位和对位)亲电取代方法的显著补充，并允许合成一些值得注意的苯稠合分子，如文献[1]。5比7。活性锂试剂预合成邻位导向基团，赋予锂离子分子内反应X‘的优势，以及锂与5分子内相互作用稳定产物的形成，似乎是导致原锂离子易于发生的原因。邻位锂化芳烃的质子化热降低(与它们的对位异构体相比，图1“)和短Li…-N和Li*…晶体1-411-14，14a中的O距离表明后一种因素的重要性，而取代基诱导的pK、四氢呋喃中单取代苯值和邻锂速率之间的差异(如强烈的锂离子活化S0，NR2只产生微弱的pk，降低效应)表明这些取代基预配位的重要性。
The new methodology (“neue Ar~ matenchemie”)~ strikingly complements the traditional electrophilic substitution approach to (mainly meta and para) polysubstituted aromatic compounds and has permitted some remarkable syntheses of benzene-fused molecules, eg refs. 5-7. Precoordination of the active lithiating agent to the ortho-directing group, which bestows on the lithiation the advantages of an intramolecular reactionX,’, and formation of a product which is stabilized by intramolecular interaction between lithium and 5 seem to be responsible for the ease of ortho-lithiation. Lowered heats of protonation of ortho-lithiated arenes (as compared to their para-isomers, Chart 1”) and short Li...-N and Li*... O distances in crystalline 1-411-14, 14a suggest the importance of the latter factor, while discrepancies between substituent induced pK, values of monosubstituted benzenes in THF and rates of ortho-lithiation (eg strongly lithiation activating S0, NR2 exerts only a weak pK, lowering effect) point to the importance of precoordination by these sub-~ tituents’~.