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ChemicalBook CAS DataBase List 6-BROMO-2H-1,4-BENZOXAZIN-3(4H)-ONE
24036-52-0

6-BROMO-2H-1,4-BENZOXAZIN-3(4H)-ONE synthesis

12synthesis methods
-

Yield: 85%

Reaction Conditions:

Stage #1:4-bromo-2-nitrophenol;ethyl bromoacetate with potassium carbonate in acetonitrile for 2 h;Reflux;
Stage #2: with iron;acetic acid at 80; for 2 h;

Steps:

1.A Step A
Compound 7-1 (25g, 0.12mol) was dissolved in CH3CN (250ml), add K2CO3 (42g, 0.23mol) and ethyl 2-bromoacetate (30g, 0.18mol). The mixture was stirred at reflux for 2h, filtered, and the filtrate was concentrated to give crude product. The crude product was dissolved in acetic acid (250ml), was added Fe (20g, 0.36mol). The mixture was stirred at 80 2h, then poured into water, extracted with ethyl acetate (3x 200ml), then washed, separated and purified by silica gel column chromatography aq.NaHCO3 (6N) (EtOAc / PE = 1: 1) to give a yellow solid compound 7-2 (22.2g, 85%).

References:

Ningbo Wenda Pharmaceutical Technology Co., Ltd;Wang, Nenghui CN106146482, 2016, A Location in patent:Paragraph 0115; 0116; 0117

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