On treatment with ammonia, primary amines, and pyrrolidine, 5,7-dimethyl-2-trifluoromethyl-8-azachromone undergoes ring opening to give beta-aminovinyl ketones. The reactions with morpholine and piperidine proceed as addition to give 2-morpholino- and 2-piperidino-8-azachromanones. With ethylene diamine, diethylenetriamines, hydrazine hydrate, and hydroxylamine, this compound reacts similarly to 2-polyfluoroalkylchromones, yielding CF3-containing dihydrodiazepines, pyrazoles, and isoxazoles,with a 2-pyridone substituent.
The first synthesis of 8-aza-2-polyfluoroalkylchromones
摘要:
The condensation of 3-acetyl-4,6-dimethyl-2-pyridone with RFCO2Et in the presence of LiH in dioxane affords corresponding R-F-containing beta-diketones, whose dehydration under the action of conc. H2SO4 gives 8-aza-5,7-dimethyl-2-polyfluoroalkylchromones. (C) 2002 Elsevier Science B.V. All rights reserved.