反应详情

11.3 g. of o-phenylenediamine, 15.1 g. of 5-ethylpicolinic acid and 80 g. of polyphosphoric acid were heated at 180°-190° C. under a nitrogen gas current for 3 hours with stirring. The reaction mixture was diluted with 1,000 ml. of water and then neutralized with sodium carbonate. The resulting crystals were filtered off, dried and recrystallized from ethyl acetate to give 17.1 g. of colorless needles of the product (78% of theory). M.P. 172.5°-173° C.

1. additionThe reaction mixture was diluted with 1,000 ml
2. filtrationThe resulting crystals were filtered off
3. customdried
4. customrecrystallized from ethyl acetate
5. customto give 17.1 g