ethyl 2-(3,4-dihydro-2H-1,4-benzoxazin-3-yl)acetate

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 650 ml of ethanol are introduced into a 3 l reactor, with magnetic stirring, cooled to 0° C., 5.9 g (0.259 mol) of sodium are added slowly, in small portions, followed by successive dropwise addition of 53 g (0.259 mol) of N-(2-hydroxyphenyl)trifluoroacetamide and 50 g (0.259 mol) of 75% pure ethyl 4-bromo-2-butenoate, and the mixture is heated at 80° C. for 1.5 h. the mixture is heated at 80° C. for 1.5 h.

Conditions: temp:75.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: T3P (50% solution in EtOAc, 132.4 g, 0.208 mol) was added to 3-oxo-3,4-dihydro-2H-1,4-benzoxazine-6-carboxylic acid (22.1 g, 0.114 mol), ethyl-2-(3,4-dihydro-2H-1,4-benzoxazin-3-yl)acetate (23.0 g, 0.104 mol) and TEA (57.9 mL, 0.416 mol) in EtOAc (139 mL) at rt. The resulting mixture was stirred at 75° C. for 16 h. The resulting solution was diluted with 800 mL of EtOAc and washed with aq. sat. NaHCO3 solution (300 mL), 0.5 M HCl solution (300 mL) and brine (300 mL). The organic phase was dried over anhydrous Na2SO4, filtered and evaporated to afford crude product. The crude product was purified by re-crystallization from MeOH to afford the title compound (14.5 g, 35%) as a white solid. washed with aq. sat. NaHCO3 solution (300 mL), 0.5 M HCl solution (300 mL) and brine (300 mL) The organic phase was dried over anhydrous Na2SO4 filtered evaporated to afford crude product The crude product was purified by re-crystallization from MeOH

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 650 ml of ethanol are introduced into a 3 l reactor, with magnetic stirring, cooled to 0° C., 5.9 g (0.259 mol) of sodium are added slowly, in small portions, followed by successive dropwise addition of 53 g (0.259 mol) of N-(2-hydroxyphenyl)trifluoroacetamide and 50 g (0.259 mol) of 75% pure ethyl 4-bromo-2-butenoate, and the mixture is heated at 80° C. for 1.5 h. the mixture is heated at 80° C. for 1.5 h.

Conditions: temp:75.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: T3P (50% solution in EtOAc, 132.4 g, 0.208 mol) was added to 3-oxo-3,4-dihydro-2H-1,4-benzoxazine-6-carboxylic acid (22.1 g, 0.114 mol), ethyl-2-(3,4-dihydro-2H-1,4-benzoxazin-3-yl)acetate (23.0 g, 0.104 mol) and TEA (57.9 mL, 0.416 mol) in EtOAc (139 mL) at rt. The resulting mixture was stirred at 75° C. for 16 h. The resulting solution was diluted with 800 mL of EtOAc and washed with aq. sat. NaHCO3 solution (300 mL), 0.5 M HCl solution (300 mL) and brine (300 mL). The organic phase was dried over anhydrous Na2SO4, filtered and evaporated to afford crude product. The crude product was purified by re-crystallization from MeOH to afford the title compound (14.5 g, 35%) as a white solid. washed with aq. sat. NaHCO3 solution (300 mL), 0.5 M HCl solution (300 mL) and brine (300 mL) The organic phase was dried over anhydrous Na2SO4 filtered evaporated to afford crude product The crude product was purified by re-crystallization from MeOH