【文章名】Synthesis of ethyl pyrimidine-4-carboxylates from unsymmetrical enamino diketones and their application in the first synthesis of pyrimido[4,5-d]pyridazin-8(7H)-ones.
Synthesis of ethyl pyrimidine-4-carboxylates from unsymmetrical enamino diketones and their application in the first synthesis of pyrimido[4,5-d]pyridazin-8(7H)-ones.
[摘要]：The reaction of unsym. enamino diketones with benzamidine hydrochloride or 1H-pyrazole-1-carboxamidine monohydrochloride, afforded a series of Et 2,5-disubstituted pyrimidine-4-carboxylates in a chemoselective and highly chemoselective manner (51-86%). Reaction of these two series of pyrimidines with hydrazine monohydrate under mild conditions led to 2,5-substituted pyrimido[4,5-d]pyridazin-8(7H)-ones in high yields (81-92%).
