1, 3-Diaza-1, 3-butadienes. Synthesis and Conversion into Pyrimidines by [4π+ 2π] Cycloaddition with Electron Deficient Acetylenes. Synthetic Utility of 2-( …
…, R Villena, R Greenhouse, JM Muchowski
文献索引：Guzman; Romero; Talamas; Villena; Greenhouse; Muchowski Journal of Organic Chemistry, 1996 , vol. 61, # 7 p. 2470 - 2483
Methods have been devised to generate 1 H-1, 3-diaza-1, 3-butadienes bearing a leaving group at position-4 in latent, masked, and unprotected forms. A hallmark of these azadienes is that they undergo thermal [4π+ 2π] cycloaddition reactions with electron deficient acetylenes to give adducts which are aromatized to pyrimidine derivatives under the reaction conditions. Thus, 1-(methoxycarbonyl)-3-acylamidines 17 on heating in solution ...
