The Diels-Alder reaction of 6-alkyl-3,5-dichloro-2H-1,4-oxazin-2-ones 1 with different types of acetylenic compounds 2 is shown to be a versatile method for the generation of variously substituted 2,6-dichloropyridines. In most cases a high degree of regioselectivity and a high yield of 3,5-disubstituted 2,6-dichloropyridines 3 is obtained.
6- 烷基-
3,5-二氯-2H-1,4-恶嗪-2-酮 1 与不同类型
乙炔化合物 2 的 Diels-Alder 反应被证明是生成各种取代的 2,6-二
氯吡啶的通用方法。 在大多数情况下,可以获得高区域选择性和高产率的 3,5-二取代 2,6-二
氯吡啶 3。