4-Chloro-3-(trifluoroacetyl)- and 4-chloro-3-(methoxalyl)coumarins as novel and efficient building blocks for the regioselective synthesis of 3,4-fused coumarins
作者:Viktor O. Iaroshenko、Friedrich Erben、Satenik Mkrtchyan、Ani Hakobyan、Marcelo Vilches-Herrera、Sergii Dudkin、Alina Bunescu、Alexander Villinger、Vyacheslav Ya. Sosnovskikh、Peter Langer
DOI:10.1016/j.tet.2011.08.030
日期:2011.10
4-chloro-3-(methoxalyl)coumarins react with electron-rich aminoheterocycles, dimethyl 1,3-acetonedicarboxylate, hydrazines, alkyl thioglycolates, and methyl sarcosinate to give a variety of 3,4-heteroannulated coumarins. The starting materials were prepared by the reaction of 4-hydroxycoumarin with trifluoroacetic anhydride and methyl 2-chloro-2-oxoacetate in the presence of trimethylsilylchloride.
4-
氯-3-(三
氟乙酰基)-和4-
氯-3-(甲
氧烷基)
香豆素与富含电子的
氨基杂环,
1,3-丙酮二羧酸二甲酯,
肼,烷基
硫代
乙醇酸
酯和
肌氨酸甲
酯合成各种3, 4异环化
香豆素。在三
甲基甲
硅烷基
氯的存在下,通过
4-羟基
香豆素与
三氟乙酸酐和2-
氯-2-
氧代
乙酸甲酯的反应制备起始原料。报道了NMR研究和X射线晶体学分析。