Rational synthesis and dimensionality tuning of MOFs from preorganized heterometallic molecular complexes

Rational synthesis of a series of new heterometallic MOFs was carried out by the judicious choice of the corresponding pivalate complexes [Li 2 M 2 (piv) 6 (py) 2 ] (M = Zn 2+ , Co 2+ , piv − = pivalate anion and py = pyridine) as a source of secondary building units, {LiM(O 2 CR) 3 } and an organic tricarboxylate linker as a node defining the dimensionality of the framework by the orientation of the carboxylic group in or out of the central aromatic ring plane. Thus the trimesate (btc 3− ) linker results in 3D srs topology frameworks with intersecting systems or isolated channels, and 1,3,5-benzenetribenzoate (btb 3− ) results in layered hcb isostructural compounds additionally stabilized with H-π interactions between the layers. The layered compounds demonstrate a permanent porosity with a BET surface area of up to 688 m 2 ·g −1 with the possibility of selective gas adsorption (CO 2 over N 2 and CH 4 ). Zn-Based coordination polymers show notable color changes and drastic (up to 30 times) quenching of luminescence upon inclusion of different nitroaromatics. Rational synthesis of heterometallic MOFs was carried out by the judicious choice of pivalate complexes and a tricarboxylate linker defining their dimensionality.