Chiral Phosphoric Acids in Metal–Organic Frameworks with Enhanced Acidity and Tunable Catalytic Selectivity
| Autor: | Yan Liu, Xiaowei Wu, Hong Jiang, Yong Cui, Xing Han, Bang Hou, Wei Gong, Fan-Fan Zheng, Xu Chen, Xu Li, Jianwen Jiang |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
010405 organic chemistry
Imine Enantioselective synthesis General Medicine General Chemistry 010402 general chemistry 01 natural sciences Combinatorial chemistry Catalysis 0104 chemical sciences chemistry.chemical_compound Enantiopure drug chemistry Metal-organic framework Selectivity Brønsted–Lowry acid–base theory Phosphoric acid |
| Zdroj: | Angewandte Chemie International Edition. 58:14748-14757 |
| ISSN: | 1521-3773 1433-7851 |
| DOI: | 10.1002/anie.201908959 |
| Popis: | Chiral phosphoric acids are incorporated into indium-based metal-organic frameworks (In-MOFs) by sterically preventing them from coordination. This concept leads to the synthesis of three chiral porous 3D In-MOFs with different network topologies constructed from three enantiopure 1,1'-biphenol-phosphoric acid derived tetracarboxylate linkers. More importantly, all the uncoordinated phosphoric acid groups are periodically aligned within the channels and display significantly enhanced acidity compared to the non-immobilized acids. This facilitates the Bronsted acid catalysis of asymmetric condensation/amine addition and imine reduction. The enantioselectivities can be tuned (up to >99 % ee) by varying the substituents to achieve a nearly linear correlation with the concentrations of steric bulky groups in the MOFs. DFT calculations suggest that the framework provides a chiral confined microenvironment that dictates both selectivity and reactivity of chiral MOFs. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text