A variety of 5-mono- and 5,6-disubstituted 1,4-dihydro-4-oxonicotinates were prepared by a novel pyridine synthesis which involves thermal cyclisation of enaminomethylenemalonates 9. The intermediates 9 were readily prepared through a few steps from commercially available starting materials.
通过新颖的
吡啶合成制备各种5-单-和5,6-二取代的1,4-二氢-4-氧代
烟酸酯,所述新颖的
吡啶合成涉及烯
氨基亚
甲基丙二酸酯9的热环化。中间体9可以通过几步容易地从市售品中制备。起始材料。