Taming gases in flow Valorization of abundant gaseous feedstocks through photochemical activation

This PhD thesis focuses on the valorization of gaseous reagents through photochemical activation in continuous-flow systems, developing novel photochemical and photocatalytic methodologies to enable efficient and selective transformations. By leveraging flow technology, gaseous reagents and soluble reaction partners are brought into proximity, leading to the formation of complex molecules. Key achievements include the selective alkylation of pyridines via a photochemical hydrogen atom transfer process, direct C–H carbonylation of sp³-hybridized carbon atoms through photocatalytic generation of nucleophilic carbon-centered radicals, and the conversion of gaseous alkanes into value-added compounds through gas-gas-liquid reactions with carbon monoxide in flow. Additionally, the photocatalytic activation of light alkane gases, followed by trapping with SO₂ gas, yields reactive alkyl sulfinate intermediates, which are further used to synthesize a variety of sulfone compounds. Another significant contribution is the formal C(sp²)–H activation through thianthrenation and photoredox activation, allowing the scalable incorporation of 1,4-diketone moieties into complex arenes. Overall, this research advances synthetic methodologies and demonstrates the potential of photochemical flow technology in creating sustainable and efficient synthetic routes using gaseous reagents.