Tomce Runcevski1
SMU1
The reactivity and functionality of organic molecules in the solid state are primarily governed by weak, non-covalent interactions, which pose challenges in terms of rational control. Furthermore, organic crystals often lack the necessary mechanical properties for the development of functional materials. These challenges can be overcome by utilizing inorganic scaffolds that incorporate functional groups capable of spatially organizing organic molecules. Conversely, the presence of molecules also influences the structure and properties of the scaffolds, often leading to improvements in their properties. In this context, we present three examples highlighting the synergy between organic molecules and inorganic scaffolds. Firstly, we demonstrate how metal-organic frameworks can be employed to store and stabilize 2-aminoethanethiol (cysteamine), a thiol-based drug, is prone to oxidation in its molecular form. By binding the thiol groups to open metal sites in MOF-74, we effectively protect the drug from oxidation and enable controlled release. Next, we explore how a slight modification of the organic molecule can significantly alter the properties of the MOF. Using ethylenedithiol instead of 2-aminoethanethiol introduces defects into the MOF structure, resulting in emergent properties like luminescence that are absent in the parent framework. Furthermore, we investigate other inorganic scaffolds, such as brucite layers, that can be interspersed with organic molecules. Incorporating sorbic acid within the layers of Co(OH)2 yields a new hybrid material with modified magnetic properties. Notably, this material serves as a platform for the synthesis of atomically-precise polymers from small organic monomers, such as an analogue of natural rubber. In summary, the combination of small organic molecules with inorganic scaffolds presents promising opportunities for tailoring and enhancing properties that can be used in the design of materials to overcome the challenges of tomorrow.