The reaction of 4-methylpyrimidinium ylides (as 1,3-dipoles) with DMAD (dimethyl acetylenedicarboxylate) and DFA (diphenylacetylene) as dipolarophiles is presented. 4-Methylpyrimidinium ylides did not react with DFA. A selective route to obtain new azabicyclic structures derived from pyrimidine via the reaction of pyrimidinium ylides with DMAD is also presented. In addition to the azabicyclic compounds, an unexpected betaine structure has been obtained, and a possible mechanism for the reaction pathway is proposed. A selective way to increase the proportion of azabicyclic compound or betaine was determined.
介绍了 4-
甲基嘧啶鎓酰化物(1,3-二极)与
DMAD(二甲基
乙炔二
甲酸酯)和 DFA(
二苯基乙炔)作为二极亲和剂的反应。4
甲基嘧啶鎓酰化物没有与 DFA 发生反应。此外,还介绍了通过
嘧啶鎓酰化物与
DMAD 的反应获得源自
嘧啶的新型
氮杂双环结构的选择性路线。除了氮杂
双环化合物外,还获得了一种意想不到的
甜菜碱结构,并提出了反应途径的可能机制。确定了增加氮
杂环化合物或
甜菜碱比例的选择性方法。