One-pot approach to the synthesis of novel 12H-chromeno[2′,3′:4,5]imidazo[1,2-a]pyridines in aqueous media
作者:M. Fernanda Proença、Marta Costa
DOI:10.1016/j.tet.2010.04.059
日期:2010.6
The chromeno-imidazo[1,2-a]pyridine scaffold was generated in an one pot condensation/cyclization reaction involving a salicylaldehyde and 1-(cyanomethyl)pyridiniumchloride, in aqueous sodium carbonate solution. These novel compounds were isolated in 47–71% yield. The reaction pathway was followed by 1H NMR spectroscopy allowing a clear understanding of the side reactions involved in the process.
在包含水杨醛和1-(氰甲基)吡啶鎓氯化物的一锅缩合/环化反应中,在碳酸钠水溶液中生成了铬诺-咪唑并[1,2- a ]吡啶骨架。这些新型化合物的分离产率为47-71%。反应路径之后是1 H NMR光谱,可以清楚地了解该过程中涉及的副反应。 合成了不同的单取代吡啶鎓氯化物,并使其与单取代水杨醛反应,并对该合成方法的范围进行了详细讨论。
Selective synthesis of some imidazopyridine-fused chromones
作者:Marta Costa、M. Fernanda Proença
DOI:10.1016/j.tet.2011.09.054
日期:2011.11
A fused heterocyclic scaffold combining the imidazo[1,2-a]pyridine with a substituted chromone was synthesized in a one-pot procedure. The reaction proceeds by intramolecular cyclization of 1-(2-imino-2H-chromen-3-yl)pyridinium chloride in ethanol and in the presence of DABCO. A detailed study of the experimental conditions allowed a clear understanding of the reaction pathway.
通过一锅法合成了结合有咪唑并[1,2- a ]吡啶和取代的色酮的稠合杂环支架。该反应通过在乙醇中和在DABCO存在下将1-(2-亚氨基-2 H-铬-3-基)吡啶鎓氯化物进行分子内环化而进行。对实验条件的详细研究可以清楚地了解反应途径。
Synthesis of 2-aminochromene derivatives from 1-(2-imino-2H-chromen-3-yl)pyridin-1-ium perchlorates and nitromethane in basic medium
作者:Olga А. Storozhenko、Xiaoyi Yue、Alexey А. Festa、Alexey А. Varlamov、Leonid G. Voskressensky
DOI:10.1007/s10593-020-02793-3
日期:2020.9
1-(2-imino-2H-chromen-3-yl)pyridinium perchlorates and nitromethane by the action of DBU at reflux in trifluoroethanol. The starting 2-iminochromenes are readily accessible from the corresponding salicylic aldehydes and quaternary cyanomethyl pyridinium salts. The reaction is tolerant to substituents of different nature (alkyl, alkoxy, halogen); a limitation is the presence of strong electron-withdrawing substituents