Regioselective Synthesis of 2- and 3-Substituted Imidazo[1,2-<i>a</i>]pyridines
作者:Guoping Liu、Xuefeng Cong、Jiaheng He、Shunzhong Luo、Di Wu、Jingbo Lan
DOI:10.3184/174751912x13499663832261
日期:2012.12
A range of 2- or 3-substituted imidazo[1,2- a]pyridines were prepared from 2-aminopyridine derivatives and gem-dibromovinyl compounds by the tandem nucleophilic substitution (or nucleophilic addition)/cyclisation reaction.
N-Heterocyclic carbene–palladium(<scp>ii</scp>)–1-methylimidazole complex catalyzed direct C–H bond arylation of imidazo[1,2-a]pyridines with aryl chlorides
We herein reported the N-heterocyclic carbene–palladium(II)–1-methylimidazole complex catalyzed direct C–H bond arylation of imidazo[1,2-a]pyridines with aryl chlorides. Under suitable conditions, all reactions between various imidazo[1,2-a]pyridines and aryl chlorides worked well to give the desired C3–H arylated products in acceptable to high yields, giving a convenient and alternative method for
我们在本文中报道了N-杂环卡宾-钯(II)-1-甲基咪唑配合物催化的咪唑并[1,2- a ]吡啶与芳基氯化物直接进行CH键芳构化。在合适的条件下,各种咪唑并[1,2- a ]吡啶与芳基氯化物之间的所有反应均能很好地产生所需的C3-H芳基化产物,并且收率高,从而为直接的C-H键提供了一种方便且可替代的方法使用经济且容易获得的芳基氯化物作为芳基化试剂,使咪唑并[1,2- a ]吡啶进行芳基化。
Synthesis of 3-Arylimidazo[1,2-a]pyridines by a Catalyst-Free Cascade Process
作者:Xiangge Zhou、Zhiqing Wu、Yinyin Pan
DOI:10.1055/s-0030-1260669
日期:2011.7
A simple and efficient protocol to synthesize 3-arylimidazo[1,2-a]pyridines by a catalyst-free cascade process from 2-aminopyridine and 1-bromo-2-phenylacetylene or 1,1-dibromo-2-phenylethene in yields up to 86% is described.
Metal- and base-free synthesis of imidazo[1,2-<i>a</i>]pyridines through elemental sulfur-initiated oxidative annulation of 2-aminopyridines and aldehydes
作者:Jing Tan、Penghui Ni、Huawen Huang、Guo-Jun Deng
DOI:10.1039/c8ob00981c
日期:——
The elemental sulfur-promoted oxidative cyclization reaction for the efficient synthesis of substituted imidazo[1,2-a]pyridines has been developed. Easily available 2-aminopyridines and aldehydes were directly assembled in a highly atom-economical fashion through oxidative annulation under metal- and base-free conditions. Besides arylacetaldehydes, aliphatic aldehydes were also compatible with this
已经开发出用于有效合成取代的咪唑并[1,2- a ]吡啶的元素硫促进的氧化环化反应。容易获得的2-氨基吡啶和醛类在无金属和无碱条件下通过氧化环化法以高度原子经济的方式直接组装。除芳基乙醛外,脂族醛也与该体系相容,以具有克级合成能力的优异收率递送烷基取代的咪唑并[1,2- a ]吡啶。
Metal-free, base catalyzed oxidative amination and denitration reaction: Regioselective synthesis of 3-arylimidazo[1,2-a]pyridines
作者:Elango Sankari Devi、Anitha Alanthadka、Subbiah Nagarajan、Vellaisamy Sridharan、Chockalingam Uma Maheswari
DOI:10.1016/j.tetlet.2018.08.024
日期:2018.9
metal-free, regioselective strategy for the synthesis of 3-arylimidazo[1,2-a]pyridines from β-nitrostyrenes and 2-aminopyridines using triethylamine as the catalyst and H2O2 (30% aq.) as the oxidant is reported. The use of an inexpensive base and facile reaction conditions make this strategy a practical alternative for the synthesis of 3-arylimidazo[1,2-a]pyridines.
使用三乙胺作为催化剂,以H 2 O 2(30%水溶液)为氧化剂,从金属上合成β-硝基苯乙烯和2-氨基吡啶的3-芳基咪唑并[1,2- a ]吡啶的无金属区域选择性策略是报告。使用廉价的碱和容易的反应条件使该策略成为合成3-芳基咪唑并[1,2- a ]吡啶的实用替代方法。