Synthesis of pyrazine acetals by the biased reaction of symmetric 2,5-bis(chloromethyl) or 2,3,5,6-tetrakis(chloromethyl) substituents on pyrazine ring with sodium alkoxides
作者:Yusaku Eda、Yuta Odazaki、Akira Mizutani、Yoshio N. Ito、Toshio Kawato
DOI:10.1016/j.tetlet.2008.02.119
日期:2008.4
2,5-Bis(chloromethyl)pyrazine reacted with sodium alkoxide to give unexpected 2-dialkoxymethyl-5-methylpyrazine along with normal substitution product, 2,5-bis(alkoxymethyl)pyrazine. The reaction of 2,3,5,6-tetrakis(chloromethyl)pyrazine with sodium alkoxide afforded similar results to yield 2,6-bis(dialkoxymethyl)-3,5-dimethylpyrazine along with other alkoxymethylpyrazines. The ratio of products depended
2,5-双(氯甲基)吡嗪与烷氧基钠反应生成未预期的2-二烷氧基甲基-5-甲基吡嗪以及2,5-双(烷氧基甲基)吡嗪。2,3,5,6-四(氯甲基)吡嗪与烷氧基钠的反应得到了相似的结果,与其他烷氧基甲基吡嗪一起生成了2,6-双(二烷氧基甲基)-3,5-二甲基吡嗪。产物的比例取决于所用的溶剂和醇盐。给出了在基本条件下这种吡嗪缩醛合成机理的一般讨论。