| In recent years,visible-light-promoted organic synthesis has attracted extensive attention from chemists because of its mild reaction conditions and environmentally friendly.Great progress has been made in the functionalization of organic compounds by visible-light-promoted radical reactions.Amino acids,as rich and cheap basic chemical substances,have attracted more and more attention due to their ability to decarboxylate under visible light to form α-amino radicals,which then react to form new and valuable C-C bonds.In this paper,the decarboxylation reactions of glycine derivatives induced by visible light were summarized,and the radical coupling reactions between N-arylglycine and carbonyl compounds or imines were studied.1.A general and efficient visible-light photoredox-catalyzed decarboxylative radical coupling reaction of N-aryl amino acids with aldehydes or ketones has been developed.This protocol used readily available materials to synthesize 41 1,2-amino alcohols with up to 98% yield by using water as the solvent at room temperature with the irradiation of blue light.This method is of some advantages including broad substrate scopes,mild reaction conditions and amenability to gram-scale synthesis,which opens up a simple,mild but effective way to produce 1,2-amino alcohols.It was note worthy that when the reaction was performed under ambient sunlight in water,it could still provide desired product with high efficiency,which further demonstrated the the practicability and green sustainability of this photocatalyzed strategy.2.A visible-light-induced and photoredox-catalyzed three-component selectivity controllable radical reaction of the readily available carbonyl compounds,amines and glycine derivatives has been studied.36 vicinal diamine and 29 imidazoline derivatives could be obtained selectively in moderate to excellent yields by varying the reaction solvent and oxidant.After series of experimental studies,we discussed the mechanism of the reaction.It is believed that under the condition of oxidation,the produced diamines can further react with formaldehyde to afford imidazolines.This strategy showed some advantages of mild conditions,high reaction efficiency and good chemical selectivity.In addition,this protocol was successfully applied in the construction of the mianserine skeleton. |
