无溶剂微波辐射下的Knoevenagel缩合反应

采用固体氢氧化钠为催化剂,在无溶剂微波辐射下芳香醛与活泼亚甲基化合物发生knoevenagel缩合反应,合成了一系列苄叉基化合物,测定了产物的熔点,并利用红外光谱、核磁共振及质谱对部分产物的结构进行了表征;同时对微波加速反应的机理进行了探讨.结果表明,该方法不但化学选择性好、反应时间短(1.5～4 min)、产率高(73%～95%),而且产物易处理,对环境污染小.

Knoevenagel Condensation in Solvent Free Condition Under Microwave Irradiation

The Knoevenagel condensation products from active methylene compounds and aromatic aldehydes with solid sodium hydroxide as catalyst were synthesized in free-solvent system under microwave lrradiation.Melting point of products were measured,structure of some products were analyzed by IR,NMR and MS.The microwave Promoting reaction mechanism has been discussed.All the reactions occur not only with good chemical selectivity,excellent yields (73%～95%)and short time ( 1.5～4 min),but also friendly to environment and easy workup.