L-proline modulated zirconium metal organic frameworks: Simple chiral catalysts for the aldol addition reaction
L-proline modulated zirconium metal organic frameworks: Simple chiral catalysts for the aldol addition reaction
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DOI：
10.1016/j.jcat.2018.06.013
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发表时间：
2018-09-01
影响因子：
7.3
通讯作者：
Van der Voort, Pascal
中科院分区：
文献类型：
--
作者：
Feng, Xiao;Jena, Himanshu Sekhar;Van der Voort, Pascal
合成了三种L-脯氨酸调节的锆基MOFs，分别命名为UiO-66、Zr-NDC（NDC = 2，6-萘二甲酸酯）和UiO-67，并对其进行了表征，考察了它们作为非对映选择性醛醇加成反应的催化性能。在L-脯氨酸的调制下，手性被引入到这些Zr-MOFs中，从而被探索作为不对称反应的手性催化剂。进行了系统的研究，以了解合成温度对每个Zr-MOF中的调制的影响。在120 ° C下合成的经调节的UiO-66材料表现出完全转化率和良好的非对映选择性，而均相L-脯氨酸催化剂仅显示61%的转化率和相反的非对映选择性。该催化剂没有表现出催化活性物质的浸出，并重复使用至少三个额外的循环。所观察到的高催化活性是与L-脯氨酸配位的Zr-节点的吸电子性质的结果。(C)2018爱思唯尔公司All rights reserved.
Three L-proline modulated zirconium based MOFs denoted as UiO-66, Zr-NDC (NDC = 2,6-Naphthalene dicarboxylate) and UiO-67 were synthesized, characterized and explored as heterogeneous catalyst in diastereoselective aldol addition reactions between 4-nitrobenzaldehyde and linear/cyclic ketones. Upon L-proline modulation, chirality was introduced into these Zr-MOFs which were consequently explored as chiral catalysts for asymmetric reactions. A systematic study was conducted to look into the effect of the synthesis temperature on the modulation in each Zr-MOF. The modulated UiO-66 material synthesized at 120 degrees C exhibited full conversion and a good diastereoselectivity whereas the homogeneous L-proline catalyst showed only 61% conversion and a reversed diastereoselectivity. The catalyst exhibited no leaching of the catalytically active species and was reused for at least three additional cycles. The observed high catalytic activity is a result of the electron withdrawing nature of the Zr-node coordinated to L-proline. (C) 2018 Elsevier Inc. All rights reserved.