反应详情

温度

80 °C

A solution of 2-methyl-quinolin-8-ol (536 mg, 3.37 mmol) in dioxane (8 mL) was added dropwise over 3 h into a stirred mixture of SeO2 (665 mg, 5.99 mmol) in dioxane (25 mL) at 50-55° C. The resulting mixture was then heated at 80° C. for 16 h, cooled, and the solids filtered off. The filtrate was concentrated and the residue purified by column chromatography on silica (dichloromethane/MeOH, 1:0-40:1). This afforded 8-hydroxy-quinoline-2-carboxaldehyde 4 as a straw-coloured solid (358 mg, 61%). 4: 1H NMR (CDCl3): δ 10.24 (s, 1 H), 8.34 (d, J=8.6, 1 H), 8.22 (br, 1 H), 8.07 (d, J=8.6, 1 H), 7.64 (dd, J=7.5 and 8.0, 1 H), 7.44 (d, J=8.0, 1 H), 7.30 (d, J=7.5, 1 H). The mixture of 4 (100 mg, 0.578 mmol), NaOAc (63 mg, mmol), hydroxylamine hydrochloride (60 mg, 0.863 mmol) and water (5 mL) was heated at 100° C. for 15 min. The precipitate was isolated by filtration. This provided the title oxime (ID 969) D1 as an off-white solid (87 mg, 80%); spectral data of this compound are shown in Table 2.

1. temperaturecooled
2. filtrationthe solids filtered off
3. concentrationThe filtrate was concentrated
4. customthe residue purified by column chromatography on silica (dichloromethane/MeOH, 1:0-40:1)
5. temperaturewas heated at 100° C. for 15 min
6. customThe precipitate was isolated by filtration