Ethyl 2-(1-(3-bromophenyl)-3-oxobutan-2-ylamino)-2-oxoacetate → Ethyl 4-(3-bromobenzyl)-5-methyloxazole-2-carboxylate
反応式
[Br:1][C:2]1[CH:3]=[C:4]([CH2:8][CH:9]([NH:13][C:14](=[O:20])[C:15]([O:17][CH2:18][CH3:19])=[O:16])[C:10](=O)[CH3:11])[CH:5]=[CH:6][CH:7]=1>O=P(Cl)(Cl)Cl>[Br:1][C:2]1[CH:3]=[C:4]([CH:5]=[CH:6][CH:7]=1)[CH2:8][C:9]1[N:13]=[C:14]([C:15]([O:17][CH2:18][CH3:19])=[O:16])[O:20][C:10]=1[CH3:11]参加物
3
実験手順
The solution of ethyl 2-(1-(3-bromophenyl)-3-oxobutan-2-ylamino)-2-oxoacetate (1.0 g, 2.9 mmol) in POCl3 (10 mL) was refluxed overnight. The mixture was concentrated, treated with H2O (40 mL), neutralized with aqueous NaHCO3 and extracted with EtOAc (3×20 mL). The combined organic layers were washed with H2O (20 mL), dried over Na2SO4, filtered, and concentrated to afford the crude product, which was purified by silica gel column chromatography (EtOAc:Petroleum ether=1:5) to afford ethyl 4-(3-bromobenzyl)-5-methyloxazole-2-carboxylate as a yellow oil (0.5 g, 51%). MS (ES+) C14H14BrNO3 requires: 323, 325 found: 324 [M+H]+, 326 [M+2+H]+(1:1).