Nucleophilic aromatic substitutions on 4,5-dicyanopyridazine. Part 2: Nitrogen nucleophiles
作者:Renzo Alfini、Elisa Calamai、Antonella Salvini、Donatella Giomi
DOI:10.1016/j.tet.2013.02.052
日期:2013.4
C-nucleophiles, 4,5-dicyanopyridazine (DCP) showed remarkable reactivity as a heterocyclic electrophile at the C–4 carbon toward amino nucleophiles. Aminocyanopyridazines, the formal SNAr2 products, have been easily synthesized in satisfactory yields through the facile substitution of a CN group of DCP, that behaves as leaving group. Operating in different solvents, the best results were generally obtained
如先前关于吡咯和吲哚C-亲核试剂的报道,4,5-二氰基哒嗪(DCP)在C-4碳上对氨基亲核试剂表现出显着的杂环亲电反应性。氨基氰基哒嗪是正式的S N Ar2产物,可通过轻松取代DCP的CN基团(起离去基团的作用),以令人满意的产率轻松合成。在不同溶剂中操作时,通常使用中等极性溶剂(如THF)可获得最佳结果。将氨基官能团引入哒嗪系统可以使原料脱对称化,并为进一步的合成精细化开辟了道路。