Phosphorus oxybromide → ethyl 6-bromo-2-methylpyridine-3-carboxylate

反応式

[CH3:1][C:2]1[NH:3][C:4](=O)[CH:5]=[CH:6][C:7]=1[C:8]([O:10][CH2:11][CH3:12])=[O:9].P(Br)(Br)([Br:16])=O.C([O-])(O)=O.[Na+]>>[Br:16][C:4]1[CH:5]=[CH:6][C:7]([C:8]([O:10][CH2:11][CH3:12])=[O:9])=[C:2]([CH3:1])[N:3]=1

参加物

反応物 3

HCID 24613Phosphorus oxybromide

HCID 516892Sodium Bicarbonate

HCID 3299500Ethyl 2-methyl-6-oxo-1,6-dihydropyridine-3-carboxylate

生成物 1

HCID 72212511ethyl 6-bromo-2-methylpyridine-3-carboxylate収率 93.1%

反応条件

温度: 130 °C

実験手順

Ethyl 2-methyl-6-oxo-1,6-dihydropyridine-3-carboxylate (2.0 g, 11 mmol) and POBr3 (8.9 g, 31 mmol) were mixed in one 100 mL flask, and the mixture was stirred at 130° C. for 4 hrs. The reaction mixture was cooled to room temperature and 50 g of ice water was added. The mixture was neutralized to pH=9 with aqueous NaHCO3 solution, extracted twice with EtOAc, dried over sodium sulfate, filtered and concentrated under reduced pressure to give 2.5 g (93% yield) of the desired product. LC-MS found: 244.1 (M+H)+.