Oxalic acid dihydrate → 6-Chloro-1-methylquinoxaline-2,3(1H,4H)-dione
反応式
[Cl:1][C:2]1[CH:7]=[CH:6][C:5]([NH:8][CH3:9])=[C:4]([N+:10]([O-])=O)[CH:3]=1.O.O.[C:15]([OH:20])(=O)[C:16](O)=[O:17]>C(O)C.Cl>[Cl:1][C:2]1[CH:3]=[C:4]2[C:5](=[CH:6][CH:7]=1)[N:8]([CH3:9])[C:16](=[O:17])[C:15](=[O:20])[NH:10]2参加物
実験手順
A suspension of 4-chloro-1-methylamino-2-nitrobenzene (1.73 g, 9.3 mmol) in 50 ml of ethanol was hydrogenated at room temperature and 2 atm. pressure in the presence of 5% palladium-on-carbon (0.5 g) until the theoretical amount of hydrogen was absorbed. The catalyst was filtered off, and 50 ml of IN hydrochloric acid was added to the filtrate. The acidic filtrate was evaporated to dryness and the solid residue was refluxed with oxalic acid dihydrate (1.4 g, 11 mmol) in 100 ml of 4M hydrochloric acid for 90 min. The mixture was cooled and the precipitated product was collected by filtration and washed with water, ethanol and ether to give 0.45 g (23%) of the title compound. M.p. 341.5° C. (N,N-dimethylformamide); IR (KBr): 1700, 1660 cm-1, 1H-NMR (DMSO-d6 : 3.43 (s, 3H, CH3), 6.97-7.40 (m, 3H, ArH), 12.0 (broad s, 1H, NH); MS m/z: 212 (M+ +2, 50%), 210 (M+, 100%).
後処理
- customwas hydrogenated at room temperature
- custom2 atm. pressure in the presence of 5% palladium-on-carbon (0.5 g) until the theoretical amount of hydrogen was absorbed
- filtrationThe catalyst was filtered off
- addition50 ml of IN hydrochloric acid was added to the filtrate
- customThe acidic filtrate was evaporated to dryness
- temperatureThe mixture was cooled
- filtrationthe precipitated product was collected by filtration
- washwashed with water, ethanol and ether
出典と根拠
- ORDレコード
- ord-13bd3ee29e14429297436e0fe7022926
- 出典データセット
- uspto-grants-1990_08
- 特許番号
- US04948794
反応ノート
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