微波促进碳酸钾催化一锅法合成2-氨基-3氰基-4-芳基-4H-苯并色烯衍生物

One-pot synthesis of 2-amino-4-aryl-3-cyano-4H-benzochromene derivatives catalyzed by K2CO3 under microwave irradiation

微波辐射下,乙醇溶剂中K2CO3催化芳甲醛、丙二腈和α-萘酚(或β-萘酚)三组分一锅法快速合成了一系列2-氨基-3-氰基-4-芳基-4H-苯并[h]色烯或苯并[f]色烯衍生物。以苯甲醛、丙二氰与α-萘酚的反应为模板反应,通过单因素实验方案优化了反应的工艺条件。结果表明:反应物各10mmol,催化剂K2CO31mmol,溶剂无水乙醇15ml,采用微波功率500W,80℃回流反应5min,2-氨基-3-氰基-4-苯基-4H-苯并[h]色烯(4a)的收率83.6%。在上述最佳条件下,利用取代苯甲醛代替苯甲醛,4H-苯并[h]色烯衍生物(4)产率为65.8%~89.4%。利用β-萘酚代替α-萘酚,4H-苯并[f]色烯衍生物(6)产率为67.5%~82.9%,合成产物通过熔点和红外光谱表征其结构。

A series of 2-amino-4-aryl-3-cyano-4H-benzo[h]chromene or benzo[h]chromene derivatives were synthesized by a three-component one-pot reaction of aromatic aldehydes, malononitrile and α-naphthol(or β-naphthol) with K 2 CO 3 as catalyst in anhydrous ethanol solvent under microwave irradiation. With benzaldehyde, malononitrile and α-naphthol as template reaction, the reaction conditions were optimized by single factor experiments. The results showed that 2-amino-4-aryl-3-cyano-4H-benzo[h]chromene(4a) was obtained 83.6% yield with the condition of each reactant 10 mmol, K 2 CO 3 1 mmol and anhydrous ethanol 15 ml as solvent, using microwave power 500 W, reflux reaction 5 min at 80℃. Under the best of the above conditions, using substituted benzaldehyde to replace benzaldehyde, 4H-benzo[h]chromene derivatives(4) were obtained 65.8%~89.4% yield. Using β-naphthol to replace α-naphthol, 4H-benzo[f]chromene derivatives(6) were obtained 67.5%~82.9% yield. The structures of these compound were characterized by m.p. and IR.