Novel heterogeneous catalysts based on zirconium sulfonated metal-organic framework (MOF)-supported L-proline has been developed for the asymmetric aldol reaction. In this study, a chiral zirconium-based sulfonated MOF-proline was assembled through the solvothermal reaction of ZrCl₄ with a combination of benzene-1,4-dicarboxylic acid (H₂bdc) and sodium 4-carboxy-2-sulfobenzoate (H₂bdc-SO₃Na) in the presence of L-proline. The MOF showed excellent crystallinity, high porosity and thermal stability, making it an attractive catalyst for the aldol reaction since the bifunctionality can be enhanced to act both as Brønsted acid and Lewis base active sites. The reaction between acetone and two different aldehydes was investigated and the catalyst showed good activity and enantioselectivity, especially in the reaction with 4-nitrobenzaldehyde (83 % enantiomeric excess and 85 % conversion). The reusability of the catalyst was evaluated by organic solvent nanofiltration membranes. After three successive aldol reactions, the enantiomeric excess and conversion reaction of the catalyst showed only slight decreases, confirming good recyclability. Moreover, scale-up of the organic solvent nanofiltration membrane operation is relatively simple, promoting ease of operation on an industrial scale.

已经开发了基于锆磺化金属-有机骨架（MOF）负载的L-脯氨酸的新型多相催化剂，用于不对称的羟醛反应。在这项研究中，通过ZrCl ₄与苯-1,4-二羧酸（H ₂ bdc）和4-羧基-2-磺基苯甲酸钠（H ）的溶剂热反应组装了手性锆基磺化MOF-脯氨酸₂ bdc-SO ₃Na）在L-脯氨酸存在下。MOF表现出出色的结晶度，高孔隙率和热稳定性，使其成为羟醛反应的引人注目的催化剂，因为双官能度可以增强以充当布朗斯台德酸和路易斯碱活性位。研究了丙酮与两种不同醛之间的反应，该催化剂表现出良好的活性和对映选择性，特别是在与4-硝基苯甲醛的反应中（对映体过量为83％，转化率为85％）。通过有机溶剂纳滤膜评估催化剂的可重复使用性。在三个连续的醛醇缩合反应之后，催化剂的对映体过量和转化反应仅显示出轻微的降低，证实了良好的可回收性。而且，有机溶剂纳滤膜操作的规模放大相对简单，