氯球嫁接L-脯氨酸绿色催化合成香豆素-3-羧酸酯

Green catalyzed synthesis of coumarin-3-carboxylate by grafting L-proline on PS

将L-脯氨酸嫁接在树脂氯球上,催化水杨醛及其衍生物和丙二酸酯直接合成香豆素-3-羧酸酯类物质,反应具有选择性强、产率高、成本低、三废少、后处理简单、催化剂可以多次重复使用等优点,符合绿色催化的特性。实验表明:反应在100℃下,醛和酯的摩尔比为1:1.2,催化剂的用量1 g,10 mL DMF中反应5h,反应的选择性≥98%,产率高达92%;催化剂循环使用6次反应的产率仍在85%以上。在此优化的反应条件下,高效合成了一系列其他香豆素-3-羧酸酯类物质,产品的结构和纯度通过了NMR、IR和熔点等手段进行了鉴定。

The synthesis of coumarin-3-carboxylic acid esters from salicylaldehyde or its derivatives and diester malonate were catalyzed by grafting L-proline onto PS.The green nature of such methodology was proven by characteristics of remarkable selectivity,high yield,low cost,less waste,simple work-up and reusability of the catalyst.It was shown that when the molar ratio of aldehyde to ester was 1:1.2,and the catalyst dosage was 1 g in 10 mL DMF at 100 ℃ for 5 h,the product selectivity was above 98%,and the yield surpassed 92%.The yield still exceeded 85% after recycling for 6 times.Under the optimized reaction conditions,a series of coumarin-3-carboxylate esters were synthesized,the identity and purity of which were characterized by NMR,IR and melting point analyses.