杂环乙炔缩醛的化学:通过DABCO催化串联环构法构建咪唑并(吡啶基)[1,2- a ]吡啶和咪唑并(吡啶基)[3,2,1- ij ] [1,8]萘啶
摘要:
具有四个反应位点的2-(2-氯代芳酰基)亚甲基咪唑烷显示出令人着迷的结构特征,可以用作合成新杂环的新策略。本文介绍了我们的新发现,在2-(2-氯芳酰基)亚甲基咪唑烷与烯丙酸酯的反应中,通过DABCO催化串联环合提供官能化的咪唑并(吡啶基)[1,2- a ]吡啶。特别重要的是掺入ø卤代组成的2-benzoylmethylene-咪唑烷芳基环,以建立一个方便的和一般的方式用于构造不寻常的咪唑并(吡啶基)[3,2,1 IJ ] [1,8萘啶。
Application of 2-(2-chloroaroyl)methyleneimidazolidines in domino and multicomponent reaction: new entries to imidazo[1,2-a]pyridines and benzo[b]imidazo[1,2,3-ij][1,8]naphthyridines
作者:Li-Rong Wen、Cui-Yu Jiang、Ming Li、Li-Juan Wang
DOI:10.1016/j.tet.2010.11.049
日期:2011.1
A new strategy for the synthesis of tetrahydroimidazo[1,2-a]pyridines and unusual tetrahydrobenzo[b]imidazo[1,2,3-ij][1,8]naphthyridines has been successfully developed by cascade reactions including Knoevenagel condensation, aza–ene reaction, imine–enamine tautomerization, cyclocondensation/oxidation, and intramolecular SNAr of precursors 2-(2-chloroaroyl)methyleneimidazolidines as new heterocyclic
通过Knoevenagel缩合,氮杂等级联反应,成功开发了合成四氢咪唑并[1,2- a ]吡啶和不寻常的四氢苯并[ b ]咪唑并[1,2,3- ij ] [1,8]萘啶的新策略。-烯反应,亚胺-烯胺互变异构,环缩合/氧化和分子内S N作为新的杂环烯酮缩醛(HKA)的前体2-(2-氯芳酰基)亚甲基咪唑烷的Ar,代表一类多官能支架,在温和条件下具有四个与芳族醛和丙二腈或2-氰基乙酸乙酯的活性反应位点。在此多米诺反应中,涉及9个不同的活性位点,并构建了2个C–C键,2个C–N键和2个新的环,所有反应物均有效地用于化学转化。
Four-Component Cascade Heteroannulation of Heterocyclic Ketene Aminals: Synthesis of Functionalized Tetrahydroimidazo[1,2-<i>a</i>]pyridine Derivatives
synthesize imidazo[1,2-a]pyridines and imidazo[1,2,3-ij][1,8]naphthyridine derivatives incorporating medicinally privileged heterosystems from heterocyclic ketene aminals, aldehydes, diketene, and amines via cascade reactions, including diketene ring-opening, Knoevenagel condensation, aza–ene reaction, imine–enamine tautomerization, cyclocondensation, and intramolecular SNAr. This strategy can provide
已开发出一种有效,简单的四组分合成方案,用于从咪唑并[1,2,3- a ]吡啶和咪唑并[1,2,3- ij ] [1,8]萘啶衍生物中合成杂环烯酮缩醛的医学优势杂化体系,醛,双烯酮和胺通过级联反应,包括双烯酮开环,Knoevenagel缩合,氮杂-烯反应,亚胺-烯胺互变异构,环缩合和分子内S N Ar。该策略可提供另一种方法,以轻松获得高度取代的咪唑并[1,2- a在温和条件下使用四个简单易用的结构单元,可以中等至良好的产率合成]吡啶衍生物。重要的是,通过在NMR分析中改变温度,可以合理地解释衍生自芳基环上带有邻卤素原子的杂环烯酮缩醛的产物在1 H NMR光谱中的异常分裂峰。
Acid/base-controlled chemodivergent synthesis of two differently functionalized tetrahydroimidazo[1,2-a]pyridines
作者:Wei-Si Guo、Xing Xin、Ke-Long Zhao、Li-Rong Wen、Ming Li
DOI:10.1039/c5ra13395e
日期:——
Two differently substituted type of imidazo[1,2-a]pyridine derivatives were synthesized chemodivergently using β-ketothioamides, aldehydes and heterocyclic ketene aminals through acid/base regulation.
Modulating the Reactivity of Heterocyclic Ketene Aminals in MCR: Selective Construction of Tetrahydrobenzo[<i>b</i>]imidazo[3,2,1-<i>ij</i>][1,8]naphthyridines
作者:Li-Rong Wen、Chao Liu、Ming Li、Li-Juan Wang
DOI:10.1021/jo101454q
日期:2010.11.19
Two new kinds of tetrahydrobenzo[b]imidazo[3,2,1-iota j][1,8]naphthyndine derivatives have been successfully synthesized by cascade reactions including Knoevenagel condensation, aza-ene reaction, imine-enamine tautomenzation, cyclocondensation, and intramolecular SNAr of precursors 2-(2-chloroaroyl)methyleneimidazolidines with aromatic aldehydes and ethyl acetoacetate or Meldrum's acid under mild conditions, respectively These studies highlighted the concept of a substrate-design approach to the development of novel multicomponent reactions by simply incorporating an o-halo group into the aryl ring of 2-benzoyl-methyleneimidazolidine as new synthons In this domino reaction, at least six different active sites are involved, two C-C bonds, two C-N bonds, and two new rings are constructed with all reactants efficiently utilized in the chemical transformation