反应详情

5-Nitro-2-phenyloxazolo[ 5,4-b]pyridine (1.2 g.) in 75 ml. of methanol, 75 ml. of benzene, 5 ml. of acetic acid and 8 ml. of 37% formaldehyde solution was hydrogenated over 1.5 teaspoonsful of Raney nickel. The catalyst was removed by filtration and the filtrate was diluted with 10 ml. of water and basified with solid sodium bicarbonate. The mixture was concentrated to dryness. The residue was crystallized from ethyl acetate to give 5-dimethylamino-2-phenyloxazolo-[ 5,4-b]pyridine, m.p. 127°-129° C.

1. customThe catalyst was removed by filtration
2. additionthe filtrate was diluted with 10 ml
3. concentrationThe mixture was concentrated to dryness
4. customThe residue was crystallized from ethyl acetate