Chloroacetyl chloride → Methyl 3-oxo-3,4-dihydro-2H-1,4-benzoxazine-6-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a mixture of methyl-3-amino-4-hydroxybenzoate (105 g, 0.62 mol) and benzyltriethylammonium chloride (142 g, 0.62 mol) in dry CHCl3 (1.5 L) was added NaHCO3 (211 g, 2.5 mol) with stirring. The reaction mixture was cooled to −5° C., added chloroacetylchloride (85 g, 0.75 mol) in dry CHCl3 (350 mL) over a period of 1.5 h at the same temperature. The reaction mixture was then heated to 55° C. for 16 h. The solvent was removed under vacuum, added water (3 L) and filtered off the solid. The solid product was dried and recrystallised from ethanol to give methyl-3-oxo-3,4-dihydro-2H-1,4-benzoxazin-6-carboxylate (108 g, 83%).

Provenance & Evidence