5-bromo-2-fluoro-3-methylbenzaldehyde

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

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

Procedure: To a solution of 5-bromo-2-fluorotoluene 169 (1.0 g, 5.29 mmol.) in anhydrous THF (4 mL) cooled in dry ice/acetone bath was added a 2 M solution of lithium diisopropylamide (2.6 mL, 5.2 mmol.). The reaction mixture was stirred for 1 hour in the dry ice/acetone bath. Anhydrous dimethylformamide (0.46 g, 6.35 mmol.) was added in a dropwise manner. The reaction mixture was allowed to warm to room temperature in 3 hours. Ethyl acetate (100 mL) was added. The organic layer was washed with 1 N hydrochloric acid, water and brine. The organic layer was dried over sodium sulfate. The organic solvent was evaporated under reduced pressure to afford 5-bromo-2-fluoro-3-methylbenzaldehyde 170 (1.08 g, 4.98 mmol.). The crude product was used in the next step without further purification. The organic layer was washed with 1 N hydrochloric acid, water and brine The organic layer was dried over sodium sulfate The organic solvent was evaporated under reduced pressure

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

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

Procedure: To a stirred suspension of pyridinium chlorochromate (3.77 g, 17.1 mmol) and silica gel in 25 ml dichloromethane was added a solution of (5-bromo-2-fluoro-3-methylphenyl)methanol in 25 mL dichloromethane. The reaction was stirred for 30 minutes at room temperature. Added additional silica gel and concentrated to adsorb reaction products onto the silica gel. Flash chromatographed (80 g silica, 5-10% ethyl acetate/hexanes gradient) to yield 2.1 g of 5-bromo-2-fluoro-3-methylbenzaldehyde as a white solid. 1H NMR (400 MHz, CDCl3) δ ppm 2.31 (d, J=2.15 Hz, 3 H) 7.42-7.63 (m, 1 H) 7.77 (dd, J=5.46, 2.34 Hz, 1 H) 10.27 (s, 1 H). Added additional silica gel concentrated reaction products onto the silica gel Flash chromatographed (80 g silica, 5-10% ethyl acetate/hexanes gradient)

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

Procedure: To a stirred solution of 5-bromo-2-fluoro-3-methylbenzaldehyde (3.5 g, 16.2 mmol) in ethanol (50.0 mL) were added sodium acetate (2.0 g, 24.3 mmol) and hydroxylamine hydrochloride (1.69 g, 24.3 mmol) at ambient temperature. The reaction mixture was stirred at ambient temperature for 3 h. The reaction mixture was concentrated on rotavapour to obtain crude compound, which was washed with water filtered and dried under vacuum to afford the title compound as a white solid: mp 126-127° C.; 1H NMR (400 MHz, CDCl3) δ 8.32 (s, 1H), 7.73 (d, J=2.4 Hz, 1H), 7.51 (s, 1H), 7.34 (d, J=2.4 Hz, 1H), 2.25 (s, 3H); ESIMS m/z 232.10 ([M+H]+). The reaction mixture was concentrated on rotavapour to obtain crude compound, which was washed with water filtered dried under vacuum

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of di-isopropyl amine (4.01 g, 39.88 mmol) in THF (20 mL) was added n-butyl lithium (1.6 M in hexane) (19.9 mL, 31.91 mmol) at −78° C. slowly dropwise over the period of 10 min, the reaction mixture was stirred at −78° C. for 30 min. A solution of 4-bromo-1-fluoro-2-methylbenzene (5.0 g, 26.6 mmol) in THF (30.0 mL) was added at −78° C., and the reaction mixture was stirred for 1 h at the same temperature. DMF (5.0 mL) was added and stirred at −78° C. for another 30 min. The reaction was monitored by TLC; then the reaction mixture was quenched with 1N HCl solution (aq) at 0° C. The aqueous layer was extracted with diethyl ether, washed with water and saturated brine solution. The combined organic layer was dried over anhydrous Na2SO4 and concentrated under reduced pressure to obtain the crude compound purified by flash column chromatography (SiO2, 100-200 mesh; eluting with 5% ethyl acetate/pet ether) to afford the title compound as a white solid (3.6 g, 64%); mp 48-50° C.: 1H NMR (400 MHz, CDCl3) δ 8.33 (s, 1H), 8.22 (s, 1H), 7.67 (s, 1H), 7.60 (s, 1H), 6.75 (dd, J=17.6, 10.8 Hz, 1H), 5.92 (dd, J=17.6, 10.8 Hz, 1H), 5.52 (d, J=17.6 Hz, 1H), 2.21 (s, 3H); ESIMS m/z 211.35 ([M−H]−). the reaction mixture was stirred for 1 h at the same temperature stirred at −78° C. for another 30 min then the reaction mixture was quenched with 1N HCl solution (aq) at 0° C The aqueous layer was extracted with diethyl ether washed with water and saturated brine solution The combined organic layer was dried over anhydrous Na2SO4 concentrated under reduced pressure to obtain the crude compound purified by flash column chromatography (SiO2, 100-200 mesh; eluting with 5% ethyl acetate/pet ether)

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

Procedure: To a stirred solution of 5-bromo-2-fluoro-3-methylbenzaldehyde (3.5 g, 16.2 mmol) in ethanol (50.0 mL) were added sodium acetate (2.0 g, 24.3 mmol) and hydroxylamine hydrochloride (1.69 g, 24.3 mmol) at RT. The reaction mixture was stirred at RT for 3 h. The reaction mixture was concentrated on rotavapour to obtain crude compound, which was washed with water filtered and dried under vacuum to afford the title compound as a white solid: mp 126-127° C.; 1H NMR (400 MHz, CDCl3) δ 8.32 (s, 1H), 7.73 (d, J=2.4 Hz, 1H), 7.51 (s, 1H), 7.34 (d, J=2.4 Hz, 1H), 2.25 (s, 3H); ESIMS m/z 232.10 ([M+H]+). The reaction mixture was concentrated on rotavapour to obtain crude compound, which was washed with water filtered dried under vacuum

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of di-isopropyl amine (4.01 g, 39.88 mmol) in THF (20 mL) was added n-butyl lithium (1.6 M in hexane) (19.9 mL, 31.91 mmol) at −78° C. slowly dropwise over the period of 10 min, the reaction mixture was stirred at −78° C. for 30 min. A solution of 4-bromo-1-fluoro-2-methylbenzene (5.0 g, 26.6 mmol) in THF (30.0 mL) was added at −78° C., and the reaction mixture was stirred for 1 h at the same temperature. DMF (5.0 mL) was added and stirred at −78° C. for another 30 min. The reaction was monitored by TLC; then the reaction mixture was quenched with 1N HCl solution (aq) at 0° C. The aqueous layer was extracted with diethyl ether, washed with water and saturated brine solution. The combined organic layer was dried over anhydrous Na2SO4 and concentrated under reduced pressure to obtain the crude compound purified by flash column chromatography (SiO2, 100-200 mesh; eluting with 5% ethyl acetate/pet ether) to afford the title compound as a white solid (3.6 g, 64%); mp 48-50° C.: 1H NMR (400 MHz, CDCl3) δ 8.33 (s, 1H), 8.22 (s, 1H), 7.67 (s, 1H), 7.60 (s, 1H), 6.75 (dd, J=17.6, 10.8 Hz, 1H), 5.92 (dd, J=17.6, 10.8 Hz, 1H), 5.52 (d, J=17.6 Hz, 1H), 2.21 (s, 3H); ESIMS m/z 211.35 ([M−H]−). the reaction mixture was stirred for 1 h at the same temperature stirred at −78° C. for another 30 min then the reaction mixture was quenched with 1N HCl solution (aq) at 0° C The aqueous layer was extracted with diethyl ether washed with water and saturated brine solution The combined organic layer was dried over anhydrous Na2SO4 concentrated under reduced pressure to obtain the crude compound purified by flash column chromatography (SiO2, 100-200 mesh; eluting with 5% ethyl acetate/pet ether)

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

Procedure: To a stirred solution of 5-bromo-2-fluoro-3-methylbenzaldehyde (3.5 g, 16.2 mmol) in ethanol (50.0 mL) were added sodium acetate (2.0 g, 24.3 mmol) and hydroxylamine hydrochloride (1.69 g, 24.3 mmol) at RT. The reaction mixture was stirred at RT for 3 h. The reaction mixture was concentrated on rotavapour to obtain crude compound, which was washed with water filtered and dried under vacuum to afford the title compound as a white solid: mp 126-127° C.; 1H NMR (400 MHz, CDCl3) δ 8.32 (s, 1H), 7.73 (d, J=2.4 Hz, 1H), 7.51 (s, 1H), 7.34 (d, J=2.4 Hz, 1H), 2.25 (s, 3H); ESIMS m/z 232.10 ([M+H]+). The reaction mixture was concentrated on rotavapour to obtain crude compound, which was washed with water filtered dried under vacuum

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of di-isopropyl amine (4.01 g, 39.88 mmol) in THF (20 mL) was added n-butyl lithium (1.6 M in hexane) (19.9 mL, 31.91 mmol) at −78° C. slowly dropwise over the period of 10 min, the reaction mixture was stirred at −78° C. for 30 min. A solution of 4-bromo-1-fluoro-2-methylbenzene (5.0 g, 26.6 mmol) in THF (30.0 mL) was added at −78° C., and the reaction mixture was stirred for 1 h at the same temperature. DMF (5.0 mL) was added and stirred at −78° C. for another 30 min. The reaction was monitored by TLC; then the reaction mixture was quenched with 1N HCl solution (aq) at 0° C. The aqueous layer was extracted with diethyl ether, washed with water and saturated brine solution. The combined organic layer was dried over anhydrous Na2SO4 and concentrated under reduced pressure to obtain the crude compound purified by flash column chromatography (SiO2, 100-200 mesh; eluting with 5% ethyl acetate/pet ether) to afford the title compound as a white solid (3.6 g, 64%); mp 48-50° C.: 1H NMR (400 MHz, CDCl3) δ 8.33 (s, 1H), 8.22 (s, 1H), 7.67 (s, 1H), 7.60 (s, 1H), 6.75 (dd, J=17.6, 10.8 Hz, 1H), 5.92 (dd, J=17.6, 10.8 Hz, 1H), 5.52 (d, J=17.6 Hz, 1H), 2.21 (s, 3H); ESIMS m/z 211.35 ([M−H]−). the reaction mixture was stirred for 1 h at the same temperature stirred at −78° C. for another 30 min then the reaction mixture was quenched with 1N HCl solution (aq) at 0° C The aqueous layer was extracted with diethyl ether washed with water and saturated brine solution The combined organic layer was dried over anhydrous Na2SO4 concentrated under reduced pressure to obtain the crude compound purified by flash column chromatography (SiO2, 100-200 mesh; eluting with 5% ethyl acetate/pet ether)

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

Procedure: To a stirred solution of 5-bromo-2-fluoro-3-methylbenzaldehyde (3.5 g, 16.2 mmol) in ethanol (50.0 mL) were added sodium acetate (2.0 g, 24.3 mmol) and hydroxylamine hydrochloride (1.69 g, 24.3 mmol) at ambient temperature. The reaction mixture was stirred at ambient temperature for 3 h. The reaction mixture was concentrated on rotavapour to obtain crude compound, which was washed with water filtered and dried under vacuum to afford the title compound as a white solid: mp 126-127° C.; 1H NMR (400 MHz, CDCl3) δ 8.32 (s, 1H), 7.73 (d, J=2.4 Hz, 1H), 7.51 (s, 1H), 7.34 (d, J=2.4 Hz, 1H), 2.25 (s, 3H); ESIMS m/z 232.10 ([M+H]+). The reaction mixture was concentrated on rotavapour to obtain crude compound, which was washed with water filtered dried under vacuum

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of di-isopropyl amine (4.01 g, 39.88 mmol) in THF (20 mL) was added n-butyl lithium (1.6 M in hexane) (19.9 mL, 31.91 mmol) at −78° C. slowly dropwise over the period of 10 min, the reaction mixture was stirred at −78° C. for 30 min. A solution of 4-bromo-1-fluoro-2-methylbenzene (5.0 g, 26.6 mmol) in THF (30.0 mL) was added at −78° C., and the reaction mixture was stirred for 1 h at the same temperature. DMF (5.0 mL) was added and stirred at −78° C. for another 30 min. The reaction was monitored by TLC; then the reaction mixture was quenched with 1N HCl solution (aq) at 0° C. The aqueous layer was extracted with diethyl ether, washed with water and saturated brine solution. The combined organic layer was dried over anhydrous Na2SO4 and concentrated under reduced pressure to obtain the crude compound purified by flash column chromatography (SiO2, 100-200 mesh; eluting with 5% ethyl acetate/pet ether) to afford the title compound as a white solid (3.6 g, 64%); mp 48-50° C.: 1H NMR (400 MHz, CDCl3) δ 8.33 (s, 1H), 8.22 (s, 1H), 7.67 (s, 1H), 7.60 (s, 1H), 6.75 (dd, J=17.6, 10.8 Hz, 1H), 5.92 (dd, J=17.6, 10.8 Hz, 1H), 5.52 (d, J=17.6 Hz, 1H), 2.21 (s, 3H); ESIMS m/z 211.35 ([M−H]−). the reaction mixture was stirred for 1 h at the same temperature stirred at −78° C. for another 30 min then the reaction mixture was quenched with 1N HCl solution (aq) at 0° C The aqueous layer was extracted with diethyl ether washed with water and saturated brine solution The combined organic layer was dried over anhydrous Na2SO4 concentrated under reduced pressure to obtain the crude compound purified by flash column chromatography (SiO2, 100-200 mesh; eluting with 5% ethyl acetate/pet ether)