关键词: 自由基化学, 光化学, 脱羧, 酰基化, 氮杂芳烃, 无溶剂

The N-heteroaryl ketones are an important class of synthetic intermediates, and their skeletal structures are widely found in natural products, drug molecules, and materials. Acylation of N-heterocycles by keto acid decarboxylation is an effective strategy for constructing N-heteroaryl ketone compounds. However, the reported synthesis methods generally require transition-metal catalysts, a large amount of chemical oxidants, photosensitizers, etc., which limits their industrial applications. Herein, a green and practical strategy for synthesizing such compounds was reported. Blue light irradiation of the mixture of N-heteroaromatics and α-ketoacids can lead to high-yield, high selectivity, and large-scale synthesis of the corresponding acylated N-heteroarenes. This system does not require any photosensitizers, catalysts, oxidants, or solvents. In addition, it is worth noting that this system does not even require continuous blue light irradiation, only light triggering is sufficient to promote this process.

Key words: free-radical chemistry, photochemistry, decarboxylation, acylation, N-heteroarenes, solvent-free