Enzyme carbomimetics: Single site sustainable catalysts for alcohols amination

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Amines are ubiquitous in chemistry, with a global market market at more than $15 billion in 2020, and growing by more than 4% every year. They are key intermediates in the chemical industry, with extensive applications as corrosion inhibitors, agrochemicals, pharmaceuticals, detergents, fabric softeners, lubricants, polymers, and food additives. Amines are made from NH3 alkylation on the industrial scale, by alcohol alkylation, nitroarene reduction, or halide substitution. These processes require harsh conditions (>50 bar, 100-250 C), external reductants and/or emit stoichiometric amounts of hydrogen halide waste. Heterogeneous catalysts are typically used, and suffer from low selectivity and activity due to the low reactivity of NH3 compared to higher amines. The aim of the project is to use high-throughput synthetic approaches to identify single-site metals supported on nitrogen-doped carbon (MN4@C) catalysts (carbozymes) for the selective alkylation of NH3 with alcohols. Alcohols only yield H2O as a byproduct, and are abundant in biomass precursors, thus constituting ideal starting materials for large scale applications towards a more sustainable industry in a circular economy.Single-site catalysts (SSC) will solve issues associated with heterogeneous catalysts (surface poisoning, low selectivity) while ensuring a 100% metal efficiency, with carbon and nitrogen as sustainable elements that are suitable to prevent SSC degradation into oxides or carbides. Catalyst discovery will be assisted by theoretical approaches (DFT and machine learning (ML)), to identify mechanistical pathways as well as to optimise and discover new unknown catalysts (i.e. dual sites). The project will also test the best performing catalysts for flow conditions for an easier impmentation into chemical industry.