Photocatalytic Decarboxylative Alkenylation of Fatty Acids for Coproduction of Linear α-Olefin and Hydrogen with High Selectivity

Production of high-value linear α -olefins from biofatty acids is a promising approach to access value-added lubricating oil. This process necessitates endothermic β -H elimination and prohibition of facile C═C bond walking along the carbon chains at elevated temperature, which are paradoxes in catalysis. Here, we develop a photocatalytic system that assembles heterogeneous Ag/TiO 2 and homogeneous Co III cocatalyst for decarboxylative alkenylation of fatty acids to produce linear α -olefins and H 2 . The Ag/TiO 2 component catalyzes decarboxylation of biofatty acid. Density functional theory (DFT) calculations and various analytical methods have shown that the generated alkyl radical readily desorbs to the solvent due to the weak adsorption strength on Ag nanoparticles (NPs) and the solvent stabilization effect. The Co III cocatalyst in the solution can capture the alkyl radical, facilitating β -H elimination to afford α -olefins with an up to 96% yield. Moreover, H 2 is produced along with α -olefin in a 1:1 ratio. The photocatalytic system is stable for at least 5 cycles and can be extended to various carboxylic acids. This study develops an alternative route to access linear α -olefins from fatty acids.