Synthesis of β-azolyl- and β-azolylcarbonylenamines and their reactions with aromatic azides

Synthesis of 4-acetyl-substituted azoles (1,2,3-triazole, 1,2,3-thiadiazole, and 1,2-oxazole) is reported. Organocatalytic reactions of 4-acetyl-1,2,3-triazoles with aryl azides were used to obtain bis-1,2,3-triazoles containing directly linked ring systems. The reactions of 4-acetylazoles with DMF–DMA led to the formation of enamines. It was found that the acetyl and methyl groups in 4-acetyl-5-methyl-1,2,3-thiadiazole competed for the role of reactive site. The obtained enamines reacted with aryl azides, forming bisheterocycles that were linked by a carbonyl group. The structures of the synthesized compounds were proved by NMR spectroscopy, mass spectrometry, and X-ray structural analysis.