5-bromo-2,4-difluoro-3-methylaniline

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

Procedure: To a suspension of 5-bromo-2,4-difluoro-3-methylaniline (24.60 g) in 42% fluoroboric acid (150 ml) with stirring vigorously at -3° to 0° C. was added sodium nitrite (11.47 g) in water (20 ml) dropwise during 40 minutes. After stirring for 1.5 hours at 0° to 5° C., the reacting mixture was cooled with ice bath sufficiently and the resulting precipitate was collected by filtration. This precipitate was washed with small portion of water and ether and dried under reduced pressure to give the title compound (28.83 g) as pale brown prisms, mp 147°-150° C. (decompd.). After stirring for 1.5 hours at 0° to 5° C. the reacting mixture was cooled with ice bath sufficiently the resulting precipitate was collected by filtration This precipitate was washed with small portion of water and ether dried under reduced pressure

Conditions: temp:50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of iron powder (26.6 g, 100 mesh) in water (60 ml), with vigorous stirring at 50° C., was slowly added concentrated hydrochloric acid (4 ml). After hot ethanol (120 ml) was mixed, 3-bromo-2,6-difluoro-5-nitrotoluene (40 g) was added dropwise to the suspension at 75° to 78° C. during 30 minutes. The reacting mixture was refluxed for 1 hour, insoluble materials were filtered off through Celite pad, and then the materials were washed with hot ethanol. To the filtrate and washings were added ice water (400 ml) and the resulting precipitate was recrystallized from hexane to give the title compound (18.66 g) as pale brown needles, mp 68°-68.5° C. The reacting mixture was refluxed for 1 hour insoluble materials were filtered off through Celite pad the materials were washed with hot ethanol To the filtrate and washings were added ice water (400 ml) the resulting precipitate was recrystallized from hexane

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

Procedure: To a suspension of 5-bromo-2,4-difluoro-3-methylaniline (24.60 g) in 42% fluoroboric acid (150 ml) with stirring vigorously at -3° to 0° C. was added sodium nitrite (11.47 g) in water (20 ml) dropwise during 40 minutes. After stirring for 1.5 hours at 0° to 5° C., the reacting mixture was cooled with ice bath sufficiently and the resulting precipitate was collected by filtration. This precipitate was washed with small portion of water and ether and dried under reduced pressure to give the title compound (28.83 g) as pale brown prisms, mp 147°-150° C. (decompd.). After stirring for 1.5 hours at 0° to 5° C. the reacting mixture was cooled with ice bath sufficiently the resulting precipitate was collected by filtration This precipitate was washed with small portion of water and ether dried under reduced pressure

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

Procedure: To a suspension of 5-bromo-2,4-difluoro-3-methylaniline (24.60 g) in 42% fluoroboric acid (150 ml) with stirring vigorously at -3° to 0° C. was added sodium nitrite (11.47 g) in water (20 ml) dropwise during 40 minutes. After stirring for 1.5 hours at 0° to 5° C., the reacting mixture was cooled with ice bath sufficiently and the resulting precipitate was collected by filtration. This precipitate was washed with small portion of water and ether and dried under reduced pressure to give the title compound (28.83 g) as pale brown prisms, mp 147°-150° C. (decompd.). After stirring for 1.5 hours at 0° to 5° C. the reacting mixture was cooled with ice bath sufficiently the resulting precipitate was collected by filtration This precipitate was washed with small portion of water and ether dried under reduced pressure

Conditions: temp:50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of iron powder (26.6 g, 100 mesh) in water (60 ml), with vigorous stirring at 50° C., was slowly added concentrated hydrochloric acid (4 ml). After hot ethanol (120 ml) was mixed, 3-bromo-2,6-difluoro-5-nitrotoluene (40 g) was added dropwise to the suspension at 75° to 78° C. during 30 minutes. The reacting mixture was refluxed for 1 hour, insoluble materials were filtered off through Celite pad, and then the materials were washed with hot ethanol. To the filtrate and washings were added ice water (400 ml) and the resulting precipitate was recrystallized from hexane to give the title compound (18.66 g) as pale brown needles, mp 68°-68.5° C. The reacting mixture was refluxed for 1 hour insoluble materials were filtered off through Celite pad the materials were washed with hot ethanol To the filtrate and washings were added ice water (400 ml) the resulting precipitate was recrystallized from hexane

Conditions: temp:50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of iron powder (26.6 g, 100 mesh) in water (60 ml), with vigorous stirring at 50° C., was slowly added concentrated hydrochloric acid (4 ml). After hot ethanol (120 ml) was mixed, 3-bromo-2,6-difluoro-5-nitrotoluene (40 g) was added dropwise to the suspension at 75° to 78° C. during 30 minutes. The reacting mixture was refluxed for 1 hour, insoluble materials were filtered off through Celite pad, and then the materials were washed with hot ethanol. To the filtrate and washings were added ice water (400 ml) and the resulting precipitate was recrystallized from hexane to give the title compound (18.66 g) as pale brown needles, mp 68°-68.5° C. The reacting mixture was refluxed for 1 hour insoluble materials were filtered off through Celite pad the materials were washed with hot ethanol To the filtrate and washings were added ice water (400 ml) the resulting precipitate was recrystallized from hexane

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

Procedure: To a suspension of 5-bromo-2,4-difluoro-3-methylaniline (24.60 g) in 42% fluoroboric acid (150 ml) with stirring vigorously at -3° to 0° C. was added sodium nitrite (11.47 g) in water (20 ml) dropwise during 40 minutes. After stirring for 1.5 hours at 0° to 5° C., the reacting mixture was cooled with ice bath sufficiently and the resulting precipitate was collected by filtration. This precipitate was washed with small portion of water and ether and dried under reduced pressure to give the title compound (28.83 g) as pale brown prisms, mp 147°-150° C. (decompd.). After stirring for 1.5 hours at 0° to 5° C. the reacting mixture was cooled with ice bath sufficiently the resulting precipitate was collected by filtration This precipitate was washed with small portion of water and ether dried under reduced pressure

Conditions: temp:50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of iron powder (26.6 g, 100 mesh) in water (60 ml), with vigorous stirring at 50° C., was slowly added concentrated hydrochloric acid (4 ml). After hot ethanol (120 ml) was mixed, 3-bromo-2,6-difluoro-5-nitrotoluene (40 g) was added dropwise to the suspension at 75° to 78° C. during 30 minutes. The reacting mixture was refluxed for 1 hour, insoluble materials were filtered off through Celite pad, and then the materials were washed with hot ethanol. To the filtrate and washings were added ice water (400 ml) and the resulting precipitate was recrystallized from hexane to give the title compound (18.66 g) as pale brown needles, mp 68°-68.5° C. The reacting mixture was refluxed for 1 hour insoluble materials were filtered off through Celite pad the materials were washed with hot ethanol To the filtrate and washings were added ice water (400 ml) the resulting precipitate was recrystallized from hexane