7-fluoro-4H-1,4-benzoxazin-3-one

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Iron powder (36.42 g) was suspended in 5% aqueous acetic acid (69 ml) and heated to 80° C. To the suspension, a solution of ethyl 5-fluoro-2-nitrophenoxyacetate (15.86 g) in acetic acid (65 ml) and ethyl acetate (65 ml) was dropwise added, and the resultant mixture was heated at 60° to 80° C. under reflux for 3 hours. After removal of residue by filtration, the filtrate was extracted with ethyl acetate. The extract was washed with water and sodium bicarbonate solution, dried and concentrated to give 7-fluoro-2H-1,4-benzoxazin-3(4H)-one (6.82 g). m.p., 186.720 C. 1H-NMR (CDCl3 +DMSO-D6) δ ppm: 4.2 (1H, broad), 4.51 (2H, s), 6.5-7.0 (3H, m). under reflux for 3 hours After removal of residue by filtration the filtrate was extracted with ethyl acetate The extract was washed with water and sodium bicarbonate solution dried concentrated

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

Procedure: A solution of 7-fluoro-2H-1,4-benzoxazin-3(4H)-one (2.0 g) in 80% aqueous sulfuric acid (30 ml) was cooled to 0° to 5° C., and 60% nitric acid (1.6 g) was gradually added thereto at 0° to 5° C. The resultant mixture was stirred at the same temperature for 30 minutes and poured onto ice water. The precipitated crystals were collected by filtration, washed with water and dried to give 7-fluoro-6-nitro-2H-1,4-benzoxazin-3(4H)-one (2.1 g) as pale brown crystals. m.p., 205.9° C. 1H-NMR (CDCl3 +DMSO-D6) δ ppm: 3.2 (1H, broad), 4.62 (2H, s), 6.76 (1H, d, J=10 Hz), 7.6 (1H, d, J=6 Hz). at 0° to 5° C poured onto ice water The precipitated crystals were collected by filtration washed with water dried

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

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

Procedure: 7-Fluoro-2H-1,4-benzoxazin-3(4H)-one (15.8 g) was mixed with iodine monochloride (15.6 g) in acetic acid (150 ml) and heated to reflux for 36 h. The cooled mixture was treated with saturated aqueous sodium bisulfite until the color was dissipated. The solid was filtered and washed well with water. The solid was air dried and dried further by dissolution in dimethylformamide (100 ml) and evaporated to dryness under reduced pressure to give the desired product (26.3 g) contaminated with some starting material. (The reaction can be taken to completion by addition of more iodine monochloride and refluxing for 24 h longer.) The crude product was used in Step B. heated to reflux for 36 h The solid was filtered washed well with water dried dried further by dissolution in dimethylformamide (100 ml) evaporated to dryness under reduced pressure

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

Procedure: 7-Fluoro-2H-1,4-benzoxazin-3(4H)-one (15.8 g) was mixed with iodine monochloride (15.6 g) in acetic acid (150 ml) and heated to reflux for 36 h. The cooled mixture was treated with saturated aqueous sodium bisulfite until the color was dissipated. The solid was filtered and washed well with water. The solid was air dried and dried further by dissolution in dimethylformamide (100 ml) and evaporated to dryness under reduced pressure to give the desired product (26.3 g) contaminated with some starting material. (The reaction can be taken to completion by addition of more iodine monochloride and refluxing for 24 h longer.) The crude product was used in Step B. heated to reflux for 36 h The solid was filtered washed well with water dried dried further by dissolution in dimethylformamide (100 ml) evaporated to dryness under reduced pressure

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

Procedure: To 3.96 g (99 mmol) of hexanes washed 60% sodium hydride in 150 ml of N,N-dimethylformamide was added portionwise as a solid 15 g (90 mmol) of 7-fluoro-2H-1,4-benzoxazin-3(4H)-one. When the addition was complete the reaction was stirred at room temperature for 10 min, after which time 19.8 g (108 mmol) of isobutyl iodide was added. The reaction was then stirred overnight before quenching into 200 ml of water. The aqueous phase was extracted with EtOAc (2×150 ml) and the combined organics were dried over Na2SO4, filtered and evaporated in vacuo to give the desired alkylated product, as a yellow oil (13 g, 65% yield). When the addition The reaction was then stirred overnight before quenching into 200 ml of water The aqueous phase was extracted with EtOAc (2×150 ml) the combined organics were dried over Na2SO4 filtered evaporated in vacuo to give the desired alkylated product

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

Procedure: To 3.96 g (99 mmol) of hexanes washed 60% sodium hydride in 150 ml of N,N-dimethylformamide was added portionwise as a solid 15 g (90 mmol) of 7-fluoro-2H-1,4-benzoxazin-3(4H)-one. When the addition was complete the reaction was stirred at room temperature for 10 min, after which time 19.8 g (108 mmol) of isobutyl iodide was added. The reaction was then stirred overnight before quenching into 200 ml of water. The aqueous phase was extracted with EtOAc (2×150 ml) and the combined organics were dried over Na2SO4, filtered and evaporated in vacuo to give the desired alkylated product, as a yellow oil (13 g, 65% yield). When the addition The reaction was then stirred overnight before quenching into 200 ml of water The aqueous phase was extracted with EtOAc (2×150 ml) the combined organics were dried over Na2SO4 filtered evaporated in vacuo to give the desired alkylated product