Highly enantioselective immobilized prolinamide-catalyzed aldol reactions in continuous-flow systems: effect of water on the catalyst lifetime and application in the synthesis of a chiral fenpentadiol analogue
作者:Caizhen Yue、Yasuhiro Yamashita、Shū Kobayashi
DOI:10.1039/d0gc04202a
日期:——
Catalytic enantioselective aldol reactions of trifluoroacetophenones with ketones under continuous-flow conditions have been developed for the first time by using polystyrene-supported prolinamides. The robustness of the flow system was demonstrated by the continuous synthesis of a variety of trifluoromethyl carbinols in high yields with high enantioselectivities. The unusually long lifetimes (>195
通过使用聚苯乙烯负载的脯氨酰胺,在连续流动条件下,三氟苯乙酮与酮的催化对映选择性醛醇缩合反应是首次开发的。通过以高收率和高对映选择性连续合成各种三氟甲基甲醇来证明流动系统的坚固性。通过促进H 2可以达到这种流动过程异常长的寿命(> 195 h)O促进亚胺中间体在聚合物上的水解。机理研究表明,在常规间歇体系中,醛醇缩合反应具有消旋现象和固有的可逆性质,两者在连续流动条件下均被抑制。该流动过程的合成效用通过手性芬戊二醇类似物的正式连续流动合成得到了进一步证明。