Zhong-an Xu

Homochiral Metal–Organic Frameworks with Enantiopure Proline Units for the Catalytic Synthesis of β-Lactams

Two enantiopure organic ligands integrating flexible proline units and rigid isophthalate units have been rationally designed and employed for the construction of four homochiral porous metal-organic frameworks (MOFs), respectively. One pair of these MOFs is used as heterogeneous catalysts to construct β-lactam derivatives by oxidative coupling reactions.

Size-Dependent Enantioselective Adsorption of Racemic Molecules through Homochiral Metal-Organic Frameworks Embedding Helicity.

Homochiral metal-organic frameworks (HMOFs) are efficient materials for enantioselective adsorption. However, the combination of size selectivity and enantioselectivity is still a major challenge in the field of HMOFs. Herein, two enantiomorphic HMOFs built from predesigned proline-derived ligands are presented. Both of them show multiple homochiral features: they contain four different helical chains and three types of helical channels. Due to the size effect of the helical channels, each HMOF can enantioselectively adsorb methyl lactate with high ee. The results reveal a new approach toward size-dependent enantioselective separation of racemic compounds by using HMOFs built from inexpensive proline derivatives.

Synthesis and gas sorption properties of a homochiral metal–organic framework with octahedral cages

A porous homochiral metal–organic framework based on a semi-rigid proline-derived ligand has been successfully synthesized under solvothermal conditions, which is built from interesting octahedral cages and exhibits gas sorption properties.

Catenation of Homochiral Metal–Organic Nanocages or Nanotubes

Catenation based on homochiral metal-organic nanocages or nanotubes is realized in this work for the first time. A flexible enantiopure ligand is employed to assemble metal ions, with the structure-directing effect of an auxiliary ligand, a triangular-prism-like nanocage, and a nanotube successfully built. Further 0D → 3D catenation is achieved by interlocking the nanocages, and 1D → 3D catenation based on nanotubes is also presented. This work reveals extraordinary catenating architectures from molecular cages and tubes.