Volume 62, Issue 38 e202308089
Research Article

Turning on Asymmetric Catalysis of Achiral Metal-Organic Frameworks by Imparting Chiral Microenvironment

Ge Yang

Ge Yang

Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemistry, University of Science and Technology of China, 230026 Hefei, Anhui, P. R. China

These authors contributed equally to this work.

Search for more papers by this author
Wenwen Shi

Wenwen Shi

CAS Key Laboratory of Precision and Intelligent Chemistry, University of Science and Technology of China, 230026 Hefei, Anhui, P. R. China

These authors contributed equally to this work.

Search for more papers by this author
Dr. Yunyang Qian

Dr. Yunyang Qian

Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemistry, University of Science and Technology of China, 230026 Hefei, Anhui, P. R. China

Search for more papers by this author
Prof. Dr. Xiao Zheng

Corresponding Author

Prof. Dr. Xiao Zheng

CAS Key Laboratory of Precision and Intelligent Chemistry, University of Science and Technology of China, 230026 Hefei, Anhui, P. R. China

Department of Chemistry, Fudan University, 200433 Shanghai, P. R. China

Search for more papers by this author
Prof. Dr. Zheng Meng

Prof. Dr. Zheng Meng

Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemistry, University of Science and Technology of China, 230026 Hefei, Anhui, P. R. China

Search for more papers by this author
Prof. Dr. Hai-Long Jiang

Corresponding Author

Prof. Dr. Hai-Long Jiang

Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemistry, University of Science and Technology of China, 230026 Hefei, Anhui, P. R. China

Search for more papers by this author
First published: 08 August 2023
Citations: 12

Graphical Abstract

The chiral microenvironment around catalytically active metal clusters in a MOF, PCN-222(Cu), is created by simply grafting chiral molecules (R)−Cn−COOH (n=1, 2, 3). Owing to multi-level modulation such as hydrogen interaction, steric hindrance, and confinement effect caused by the microenvironment, the resulting (R)−Cn@PCN-222(Cu) exhibits high activity and enantioselectivity in the asymmetric ring-opening of cyclohexene oxide with aniline.

Abstract

The development of heterogeneous asymmetric catalysts has attracted increasing interest in synthetic chemistry but mostly relies on the immobilization of homogeneous chiral catalysts. Herein, a series of chiral metal–organic frameworks (MOFs) have been fabricated by anchoring similar chiral hydroxylated molecules (catalytically inactive) with different lengths onto Zr-oxo clusters in achiral PCN-222(Cu). The resulting chiral MOFs exhibit regulated enantioselectivity up to 83 % ee in the asymmetric ring-opening of cyclohexene oxide. The chiral molecules furnished onto the catalytic Lewis sites in the MOF create multilevel microenvironment, including the hydrogen interaction between the substrate and the chiral −OH group, the steric hindrance endowed by the benzene ring on the chiral molecules, and the proximity between the catalytic sites and chiral molecules confined in the MOF pores, which play crucial roles and synergistically promote chiral catalysis. This work nicely achieves heterogeneous enantioselective catalysis by chiral microenvironment modulation around Lewis acid sites.

Conflict of interest

The authors declare no conflict of interest.

Data Availability Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.

The full text of this article hosted at iucr.org is unavailable due to technical difficulties.