A new and efficient CuI-catalyzed dominoKnoevenagel hetero-Diels-Alderreaction of 1-oxa-1,3-butadienes with terminal unactivated acetylenesas building blocks to afford pyrano[2,3- C]pyrazoleshas been developed. The products were obtained in good to high yieldsin most cases. Synthesis of polycyclic compounds in one-pot, witheasy workup, and mild reaction conditions are advantages of ourreported method
一种新型高效的 CuI 催化 1-oxa-1,3-丁二烯与末端未活化乙炔的多米诺 Knoevenagel 异-Diels-Alder 反应作为构建单元得到吡喃并 [2,3-C] 吡唑。在大多数情况下以良好到高产率获得产物。一锅法合成多环化合物、后处理容易、反应条件温和是我们报道的方法的优点。
Trifluoroethanol as an efficient reaction media for the synthesis of pyran skeleton through domino Knoevenagel–hetero-Diels–Alder reaction with non-activated alkynes
AbstractTrifluoroethanol as an efficient media for the domino Knoevenagel–hetero-Diels–Alder reaction of O-propargyloxy benzaldehydes as non-activated terminal alkynes with some active methylene compounds has been described. Short reaction time, easy work-up, good to high yields, and mild reaction conditions are advantages of this new media. Graphical Abstract