反应详情

A solution of sodium nitrite (0.259 g, 3.75 mmol) in water (1.0 mL) was added dropwise to a solution of 6,11-dihydro-5H-dipyrido[2,3-b:3′,4′-f]azepin-5-one (0.330 g, 1.56 mmol, Intermediate D-6) dissolved in acetic acid (6.0 mL). The mixture was stirred at room temperature for 90 minutes at which time a precipitate had formed. The yellow mixture was reduced to about half original volume in vacuo, and then diluted with 20 mL water and stirred for 30 minutes. A thick precipitate formed which was collected by suction filtration, washed with water and then dried in a vacuum oven at 50° C. overnight. The desired product was obtained as a yellow powder (224 mg, 60%). (2 peaks, ˜2:1 ratio of oxime isomers). 1H NMR (DMSO-d6, ˜2:1 mixture of oxime isomers): δ 12.55 & 12.32 (bs, 1H), 11.41 & 11.18 (bs, 1H), 8.67 (m, 2H), 8.54-8.25 (m, 2H), 7.56 (m, 1H), 7.27 (m, 1H). LC/MS: 241 (M+H)+

1. customhad formed
2. stirringstirred for 30 minutes
3. customA thick precipitate formed which
4. filtrationwas collected by suction filtration
5. washwashed with water
6. customdried in a vacuum oven at 50° C. overnight