反応式
[Cl:1][C:2]1[C:3]([N+:15]([O-])=O)=[C:4]([NH:8][CH:9]([CH2:13][CH3:14])[C:10](O)=[O:11])[CH:5]=[CH:6][CH:7]=1.Cl.O.O.Cl[Sn]Cl.[OH-].[K+]>CCO>[Cl:1][C:2]1[CH:7]=[CH:6][CH:5]=[C:4]2[C:3]=1[NH:15][C:10](=[O:11])[CH:9]([CH2:13][CH3:14])[NH:8]2参加物
実験手順
To a solution of 2-((3-chloro-2-nitrophenyl)amino)butanoic acid (1.5 Kg, 5.8 mol), 4 N aq. HCl (4.35 L, 17.4 mol) and EtOH (5.3 L) was added SnCl2.2H2O (3.93 Kg, 17.4 mol). The reaction mixture was heated to reflux for 5 h. At this time LC-MS analysis showed that the reaction was complete. After cooling to rt the reaction mixture was evaporated under reduced pressure. The resulting residue was cooled to 0° C. using an ice-water bath and an aqueous solution of 10 N KOH (12 L, 180 mol) was carefully added with vigorous stirring. After filtration to remove insoluble solids, the filtrate was extracted with DCM (2×10 L) washed with water, brine, dried over anhydrous Na2SO4, and evaporated under reduced pressure to give 8-chloro-3-ethyl-3,4-dihydroquinoxalin-2(1H)-one (1.1 Kg) as a yellow solid, which was used without further purification. 1H NMR (DMSO-d6) δ ppm 9.70 (s, 1H), 6.65-6.83 (m, 3H), 6.31-6.44 (m, 1H), 3.66-3.72 (m, 1H), 1.53-1.71 (m, 2H), 0.92 (t, J=7.4 Hz, 3H). Mass Spectrum (ESI) m/z=211.2 (M+1).
後処理
- temperatureThe reaction mixture was heated
- temperatureto reflux for 5 h
- customwas evaporated under reduced pressure
- temperatureThe resulting residue was cooled to 0° C.
- filtrationAfter filtration
- customto remove insoluble solids
- extractionthe filtrate was extracted with DCM (2×10 L)
- washwashed with water, brine
- dry with materialdried over anhydrous Na2SO4
- customevaporated under reduced pressure
出典と根拠
- ORDレコード
- ord-da06148f94a5423da4a46d373abe8a77
- 出典データセット
- uspto-grants-2014_09
- 特許番号
- US08835432B2
関連ノート
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