The Love Group develops themes in molecular inorganic chemistry for a diverse range of scientific challenges.
Keywords: Transition metal and f-element chemistry related to sustainable energy processes, catalysis, supramolecular recognition and catalysis, ligand/macrocycle design, and metal recovery and recycling.
Redox Catalysis by Dinuclear and Multinuclear Pacman Complexes
Catalytic reactions involving small molecules such as O2, CO2, and N2 are important in developing sustainable chemical processes. We have designed a series of straightforwardly-prepared macrocycles that, on metallation, form rigid, wedge-shaped Pacman structures in which the primary coordination sphere and intrametallic separation are well-defined. We are studying the 1st row transition metal complexes of these macrocycles and investigating their properties in redox chemistry and catalysis.
Supramolecular Catalysis (with Prof. Fritz Kuehn and Dr Mirza Cokoja, Technical University Munich)
The outcomes of many reactions that are catalysed by transition metals are greatly influenced by the microenvironments at the metal. This is particularly true in capsules and deep-cavity complexes, which in some way mimic the active sites of metalloenzymes. This project has developed new small molecule approaches towards the synthesis of capsular, encapsulated, and dynamically-assembled metal complexes as hosts for small molecules and metal clusters, using pre-organised macrocyclic receptors and self-assembly. We are particularly interested in using these compounds as catalysts in biphasic oxidation reactions.
F-Element Chemistry (with Prof. Polly Arnold, Edinburgh)
Unlike transition metals, the oxo groups of the uranyl ion [UO2]2+ are chemically inert. However, when placed in a Pacman macrocyclic environment, we have found that new reactions of the oxo groups can be promoted, in particular leading to new O-M and O-Si bonds. Furthermore, new f-element clusters can be prepared that have unique magnetochemical properties. We are also investigating the activation of small molecules using low oxidation-state uranium Pacman complexes, evaluating other macrocyclic motifs to probe covalency in bonding, and preparing new transuranic complexes that provide insight into the properties of these unusual metals.
Metal Recovery and Recycling (with Dr Carole Morrison, Edinburgh)
The recovery of metals from their ores and secondary sources (the ‘urban mine’) by solvent extraction relies on reagents that recognize one metal from another. We are developing new reagents based on fundamental coordination and supramolecular chemistries that can recover selectively base, platinum-group, or rare-earth metals from pregnant leach solutions. These new reagents include anion receptors that pre-organise on protonation to address the outer-sphere environment of metalate anions through unusual C-H hydrogen bonds and ditopic receptors for selective loading and stripping of the platinum group metals. These projects generally involve significant input from end-users such as mining companies, refiners, and reagent suppliers.
All of these research themes involve organic and inorganic synthetic methods, and rely on a range of characterizing techniques, including NMR spectroscopy, mass spectrometry, and X-ray crystallography.