2-chloro-5-fluoro-4-methoxyaniline

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

Procedure: 2-Chloro-5-fluoro-4-methoxyaniline (14.0 g, 79.7 mmol) was cooled to 0° C. and conc. HCl (40 mL) was added over 20 min. The suspension was heated to 55° C. until the aniline was completely dissolved, then cooled back to 0° C. A solution of sodium nitrite (6.1 g, 87.7 mmol) in water (15 mL) was added dropwise over 15 min. After complete addition the mixture was stirred at 0° C. for 30 min. Hexanes (24 mL) and dichloromethane (24 mL) were added followed by a solution of potassium iodide (26.5 g, 159.4 mmol) in water (25 mL) which was added dropwise over 30 min. After stirring at 0° C. for 4 h dichloromethane (50 mL) was added and the reaction quenched with sat. aq. NaHSO3. The solution was extracted with dichloromethane. The organic layers were washed with brine, dried (Na2SO4), filtered and concentrated in vacuo to give 21 g (92%) of 1-chloro-4-fluoro-2-iodo-5-methoxy-benzene: Crude 1H NMR (400 MHz, CDCl3): δ 7.48 (d, J=10.3 Hz, 1H), 7.04 (d, J=7.8 Hz, 1H), 3.86 (s, 3H). The crude material was pure enough to carry on to the next step. was completely dissolved After complete addition the mixture was added dropwise over 30 min was added the reaction quenched with sat. aq. NaHSO3 The solution was extracted with dichloromethane The organic layers were washed with brine dried (Na2SO4) filtered concentrated in vacuo

Conditions: temp:55.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 1-Chloro-4-fluoro-5-methoxy-2-nitro-benzene (16.3 g, 79.3 mmol) and Sn granules (29.1 g, 246 mmol) were suspended in water (200 mL). Concentrated HCl (79 mL, 952 mmol) was added dropwise over 20 min. The resulting mixture was heated to 55° C. for 3 h. The solution was cooled to room temperature and carefully quenched with 1 N NaOH. The thick mixture was filtered through celite eluting the ethyl acetate to give a clear solution which was extracted with ethyl acetate. The ethyl acetate layers were washed with brine, dried (Na2SO4), filtered and concentrated in vacuo to give 26 g (80%) of 2-chloro-5-fluoro-4-methoxyaniline: Crude 1H NMR (400 MHz, CDCl3): δ 6.88 (d, J=8.3 Hz, 1H), 6.57 (d, J=12.2 Hz, 1H), 3.79 (s, 3H), 3.77 (br s, 2H). The crude material was pure enough to carry on to the next step. The solution was cooled to room temperature carefully quenched with 1 N NaOH The thick mixture was filtered through celite eluting the ethyl acetate to give a clear solution which was extracted with ethyl acetate The ethyl acetate layers were washed with brine dried (Na2SO4) filtered concentrated in vacuo