反应详情

The two-step process for producing pure 1-azaxanthone starts from 2-chloronicotinic acid which is reacted with sodium phenoxide at 160°-200° C., the mixture is dissolved in water and acidified, the 2-phenoxynicotinic acid obtained is cyclized with a dehydrating agent, usually polyphosphoric acid, at 120°-200° C. The cooled mixture is dissolved in water and neutralized with an alkaline hydroxide, and the precipitated 1-azaxanthone is washed and recrystallized.