Chiral metal-organic frameworks with a three-dimensional network structure and wide-open pores (>30 Å) were obtained by using chiral trifunctional linkers and multinuclear zinc clusters. The linkers, H(3) ChirBTB-n, consist of a 4,4',4''-benzene-1,3,5-triyltribenzoate (BTB) backbone decorated with chiral oxazolidinone substituents. The size and polarity of these substituents determines the network topology formed under solvothermal synthesis conditions. The resulting chiral MOFs adsorb even large molecules from solution. Moreover, they are highly active Lewis acid catalysts in the Mukaiyama aldol reaction. Due to their chiral functionalization, they show significant levels of enantioselectivity, thereby proving the validity of the modular design concept employed.

A bifunctional imidazolium linker was used for the production of highly crosslinked element organic frameworks by Suzuki-coupling with tetrafunctional boronic acids. The resulting porous materials are good heterogeneous organocatalysts in the N-heterocyclic carbene-catalyzed conjugated umpolung of α,β-unsaturated cinnamaldehyde.

In this work we propose an approach for the controlled synthesis of cationic frameworks by the use of imidazolium salts as linker molecules. The imidazolium salt linker H 2 ImidCl was prepared in five steps and converted with zinc and copper nitrate, respectively, to give the two topologically different cationic frameworks [Cu(Imid)(H 2 O)] + and [Zn 4 (Imid) 5 ] 3+ . The framework charge is compensated by anions located in the pores. [Cu(Imid)(H 2 O)] + shows a selective adsorption of organic molecules either bearing a carboxylic group or having an ionic nature. Furthermore, adsorbed molecules featuring a carboxylic group are captured inside the pores, whereas ionic substances can be reversibly adsorbed and desorbed, which was followed by UV/vis spectroscopy.

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