负载L-脯氨酸的温敏性共聚物的制备及其在水相中催化直接不对称Aldol反应

摘要

我们首先通过含N-boc保护手性单体与苯乙烯、N-异丙基丙烯酰胺( Nipamn) RAFT共聚，并进一步采取脱保护的方法制备一种负载L-脯氨酸的温敏性共聚物。该两亲性共聚物在水相中能够有效地催化直接不对称Aldol反应。此外，我们还研究了不同反应温度(0℃、25℃、35℃、50℃)对该催化剂的催化活性和立体选择性的影响，实验结果证明，该催化剂在其最低临界溶解温度( LCST)上下均有较高的催化活性和立体选择性，并且无论是其转化率还是ee值都能达到96%以上。%Thermoresponsive copolymer-supported L-proline catalysts were prepared by RAFT copolymerization,which used N-Boc-protection-L-proline,styrene and Nipamn as monomer and further deprotection. This thermoresponsive copolymer could be regarded as an effective catalyst for the direct asymmetric Aldol reaction in water. Furthermore,we investigated the influence of the different reaction temperatures(25℃、35℃、50℃)on the catalytic activity and stereoselectivity of catalysts. Experimental results showed that using this catalyst for the reaction in water resulted in a high conversion(96%)and ee(96%)above and below the LCST tempera-ture.