反应详情

o-Nitroaniline (0.5 mole) was diazotized in the usual manner with concentrated hydrochloric acid (200 ml.) and sodium nitrite (0.5 mole). The clear diazonium solution was added slowly to a cold solution (0-5° C.) of phenol (0.5 mole) in 450 ml. of 10% sodium hydroxide. The mixture was stirred for 1 hour and compound A filtered out (60% yield). One-tenth mole of compound A was dissolved in 100 ml. of 2N NaOH. Zinc dust (30 g.) and sodium hydroxide (50 ml. of a 25% solution) were added slowly to the well-stirred solution to keep the temperature below 45° C. The mixture was then cooled to <30° C. and acidified with concentrated hydrochloric acid. After stirring for 2 hours, the precipitate was filtered. Recrystallization from ethanol-water gave p-(2H-benzotriazol-2-yl)phenol (B) in 90% yield (mp 216°-18° ). ##STR18##

1. filtrationcompound A filtered out (60% yield)
2. dissolutionOne-tenth mole of compound A was dissolved in 100 ml
3. additionof a 25% solution) were added slowly to the well-stirred solution
4. customthe temperature below 45° C
5. temperatureThe mixture was then cooled to <30° C.
6. stirringAfter stirring for 2 hours
7. filtrationthe precipitate was filtered
8. customRecrystallization from ethanol-water