Abstract

The three-component reaction of lithiated methoxyallene, nitriles and trichloroacetic acid gave three model β-keto enamides that were starting materials for the synthesis of trichloromethyl-substituted pyridine and pyrimidine N-oxide derivatives. Upon treatment with acetic anhydride, the methyl group of the prepared pyrimidine N-oxides was converted into an acetoxymethyl group by a Boekelheide rearrangement. A few typical experiments also revealed that the trichloromethyl group of the prepared pyrimidine N-oxides can be replaced by an alkoxy or a hydroxy group, or transformed into an arylthiomethyl group. An alternative approach to β-keto enamides via the corresponding β-keto enamines was also examined and provided the expected 4-hydroxy-6-(trichloromethyl)pyridine derivative in good yield.

The three-component reaction of lithiated methoxyallene, nitriles and trichloroacetic acid gave three model β-keto enamides that were starting materials for the synthesis of trichloromethyl-substituted pyridine and pyrimidine N-oxide derivatives. Upon treatment with acetic anhydride, the methyl group of the prepared pyrimidine N-oxides was converted into an acetoxymethyl group by a Boekelheide rearrangement. A few typical experiments also revealed that the trichloromethyl group of the prepared pyrimidine N-oxides can be replaced by an alkoxy or a hydroxy group, or transformed into an arylthiomethyl group. An alternative approach to β-keto enamides via the corresponding β-keto enamines was also examined and provided the expected 4-hydroxy-6-(trichloromethyl)pyridine derivative in good yield.

中文翻译：

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三氯甲基取代的吡啶和嘧啶衍生物的制备及反应

摘要

锂化的甲氧基烯丙基，腈和三氯乙酸的三组分反应产生了三种β-酮型酰胺模型，它们是合成三氯甲基取代的吡啶和嘧啶N-氧化物衍生物的起始原料。用乙酸酐处理后，通过波克海德重排将制备的嘧啶N-氧化物的甲基转化为乙酰氧基甲基。一些典型实验还表明，制得的嘧啶N的三氯甲基基团-氧化物可以被烷氧基或羟基取代，或转化成芳硫基甲基。还研究了通过相应的β-酮烯胺替代β-酮烯酰胺的方法，并以良好的收率提供了预期的4-羟基-6-（三氯甲基）吡啶衍生物。

锂化的甲氧基烯丙基，腈和三氯乙酸的三组分反应产生了三种β-酮型酰胺模型，它们是合成三氯甲基取代的吡啶和嘧啶N-氧化物衍生物的起始原料。用乙酸酐处理后，通过波克海德重排将制备的嘧啶N-氧化物的甲基转化为乙酰氧基甲基。一些典型实验还表明，制得的嘧啶N的三氯甲基基团-氧化物可以被烷氧基或羟基取代，或转化成芳硫基甲基。还研究了通过相应的β-酮烯胺替代β-酮烯酰胺的方法，并以良好的收率提供了预期的4-羟基-6-（三氯甲基）吡啶衍生物。