Ethyl Acetate → Methyl 2,2-dimethyl-3-oxo-3,4-dihydro-2h-1,4-benzoxazine-6-carboxylate

Beteiligte Stoffe

Reaktionsschritte

To solution of 2-amino-4-methoxycarbonylphenol [Acta Chimica Academiae Scientiarum Hungaricae, 99 (1), 49-50 (1979)] (4.78 g) in a mixed solvent of ethyl acetate (50 ml) and water (50 ml) were added sodium hydrogen carbonate (3.6 g) and 2-bromoisobutyryl bromide (6.90 g) and the mixture was stirred at room temperature for 10 minutes. The organic layer was separated and the solvent was distilled off under reduced pressure. The resulting residue was dissolved in dimethylformamide (70 ml), to the solution was added potassium carbonate (4.35 g) and the mixture was stirred at room temperature for a day. The reaction solution was poured into water to give precipitates, which were taken by filtration and dried to give 2,2-dimethyl-6-methoxycarbonyl-3-oxo-3,4-dihydro-2H-1,4-benzoxazine (5.4 g).

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