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A novel heterogeneous catalyst, alkaloid@Cu was prepared by the entrapment of commercially purchased alkaloids within non-noble metallic copper nanoparticles. This composite was compacted into a coin and directly used as cathode for electrocatalytic asymmetric hydrogenation of aromatic ketones. Using water as hydrogen source, optically active alcohols with 71% ee value and 93% yield were obtained under very mild conditions. Keywords: Copper nanoparticles, Encapsulated alkaloids, Electrocatalytic hydrogenation, Asymmetric hydrogenation

Copper nanoparticles were prepared in an aqueous solution, compacted into a coin, and used as a cathode for asymmetric hydrogenation by the electrochemical method for the first time. A good ee value and excellent yield were obtained under mild conditions. Electrochemical conditions were crucial for alkaloid adsorption on metallic Cu, which is a key process of asymmetric induction. Furthermore, the ee value was linear with an adsorption amount. Keywords: Copper nanoparticles, Asymmetric hydrogenation, Electrochemical conditions, Alkaloids, Adsorption

In this paper, the one-step synthesis of enantiomerically pure cyclic carbonates has been developed by electrolyzing the chiral epoxides and CO2 (0.1 MPa, rt) in an undivided cell with a 316 stainless steel (SS) cathode and a Mg sacrificial anode containing TEAI–MeCN as supporting electrolyte and solvent with a constant current. To deeply understand this reaction, the effects of various synthesis conditions were investigated using R-styrene oxide as the model compound. Under the optimized conditions, the maximum conversion is 67% with 96% selectivity and 98.8% ee value for R-styrene carbonate. Finally, the reaction mechanism has been proposed by comparative electrolysis and DFT calculation. Keywords: Electrosynthesis, Cyclic carbonates, CO2, Chiral epoxides