We report the synthesis of novel alkyl 4-alkyl-2,8-dioxo-2H,8H-pyrano[2,3-f]chromene-10-carboxylates by the
reaction of 7-hydroxy coumarins and dialkyl acetylenedicarboxylates in the presence of triphenylphosphine, when alkyl
propiolates were employed O-vinylated coumarin derivatives were obtained.
我们报告了通过在
三苯基膦存在下,将7-羟基
香豆素与二烷基
乙炔二
羧酸酯反应,合成了新型烷基4-烷基-2,8-二氧代-2H,8H-
吡喃并[2,3-f]色烯-10-
羧酸酯。当使用烷基
丙炔酸酯时,得到了O-
乙烯基化的
香豆素衍
生物。