功能化离子液体支载脯氨酸催化的不对称Henry缩合反应

Asymmetric Henry Condensation Catalyzed by Ionic Liquid-supported Proline

以L-脯氨酸支载在功能化离子液体四氟硼酸1-（2-羟乙基）3.甲基咪唑鎓盐上的离子液体（[Promim] CF3CO2）为催化剂兼溶剂,可在温和条件下顺利地催化硝基乙烷、硝基甲烷和各种醛的Henry缩合反应,目标产物的产率达79％～ 95％,非对映选择性可达3∶1,对映选择性可达85％ ee.反应操作和后处理简单方便.[Promim] CF3CO2离子液体通过简单的处理即可实现循环利用,以邻-硝基苯甲醛和硝基乙烷为反应底物的模板反应,这种离子液体可以较稳定地循环使用6次,催化活性不降.

A functionalized ionic liquid-supported proline,1-methyl-3-{ 2-[（2s）-pyrrolidine-2-carbonyloxy] ethyl}-1H-imidazol-3-iumtrifluoroacetate（[Promim] CF3CO2）,was used to catalyze the Henry condensation reaction of aldehydes with CH3CH2NO2 or CH3NO2.The desired products were obtained in 79％ ～ 95％ yields,diastereomeric excess and enantiomeric excess was up to 3∶1 and 85％ under relatively mild conditions.[Promim] CF3CO2 could be efficiently recycled six times without the decrease of catalytic activity in the condensation reaction of 4-nitrobenzaldehyde and CH3 CH2NO2.