2',4'-Difluoropropiophenone

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 1-(2,4-difluoro-phenyl)-propan-1-one (21.29 g, 125.1 mmol) in toluene (120 mL) was added sodium acetate (26.75 g, 326.1 mmol) and cyclohexylhydrazine mesylate (34.0 g, 163 mmol). The reaction mixture was heated to reflux in a Dean-Stark apparatus for 12 hours. The reaction was cooled to room temperature and poured into 1N hydrochloric acid (100 mL). The toluene layer was separated and washed with water (75 mL) and brine (75 mL). The organic layer was dried over magnesium sulfate, filtered, and concentrated to yield 30.07 g of 1-cyclohexyl-3-ethyl-6-fluoro-1H-indazole (98% yield). 1H NMR (400 MHz, CDCl3) d 1.33 (t, 3, J=7.7), 1.35-1.44 (m, 2), 1.47-1.96 (m, 8), 2.93 (q, 2, J=7.7), 4.14-4.22 (m, 1), 6.81 (dt, 1, J=8.9, 2.1), 6.99 (dd, 1, J=9.8, 2.1), 7.40 (ddd, 1, J=8.7, 5.2, 0.4). 13C NMR (100 MHz, CDCl3) d 13.97, 20.53, 25.37, 25.84, 32.32, 58.18, 94.77 (d, J=27.4), 109.11 (d, J=26.0), 119.38, 121.75 (d, J=11.5), 139.89 (d, J=13.0), 146.61, 161.95 (d, J=242). IR 2968, 2934, 2856, 1624, 1507, 1174, 1125, 825 cm-1. Analysis calculated for C15H19FN2 : C, 73.14; H, 7.77; N, 11.37. Found: C, 73.33; H, 7.90; N, 11.46. The reaction mixture was heated to reflux in a Dean-Stark apparatus for 12 hours The toluene layer was separated washed with water (75 mL) and brine (75 mL) The organic layer was dried over magnesium sulfate filtered concentrated

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

Procedure: To a solution of 1-(2,4-difluoro-phenyl)-propan-1-one (21.29 g, 125.1 mmol) in toluene (120 mL) was added sodium acetate (26.75 g, 326.1 mmol) and cyclohexylhydrazine mesylate (34.0 g, 163 mmol). The reaction mixture was heated to reflux in a Dean-Stark apparatus for 12 hours. The reaction was cooled to room temperature and poured into 1 N hydrochloric acid (100 mL). The toluene layer was separated and washed with water (75 mL) and brine (75 mL). The organic layer was dried over magnesium sulfate, filtered, and concentrated to yield 30.07 g of 1-cyclohexyl-3-ethyl-6-fluoro-1H-indazole (98% yield). 1H NMR (400 MHz, CDCl3) d 1.33 (t, 3, J=7.7), 1.35-1.44 (m, 2), 1.47-1.96 (m, 8), 2.93 (q, 2, J=7.7), 4.14-4.22 (m, 1), 6.81 (dt, 1, J=8.9, 2.1), 6.99 (dd, 1, J=9.8, 2.1), 7.40 (ddd, 1, J=8.7, 5.2, 0.4). 13C NMR (100 MHz, CDCl3) d 13.97, 20.53, 25.37, 25.84, 32.32, 58.18, 94.77 (d, J=27.4), 109.11 (d, J=26.0), 119.38, 121.75 (d, J=11.5), 139.89 (d, J=13.0), 146.61, 161.95 (d, J=242). The reaction mixture was heated to reflux in a Dean-Stark apparatus for 12 hours The toluene layer was separated washed with water (75 mL) and brine (75 mL) The organic layer was dried over magnesium sulfate filtered concentrated

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

Procedure: To a solution of 170 g (1.00 mol) of 2,4-difluoropropiophenone in 200 g methylcyclohexane 37 g (1.01 mol) of gaseous hydrochloric acid is dosed over 3 hours at 0° C. Thereafter 120 g (1.04 mol) of pentylnitrite are added over a period 3 to 4 hours to the reaction mixture at +10° C. to +15° C. Following the end of the addition the batch is stirred for an hour at +10° C. to +15° C. during which time a suspension is formed. The reaction mixture is then cooled to 0° C. and stirred for a further hour. The product is isolated by filtration and the filter cake is washed with 75 g of methylcyclohexane at 0° C.: 176 g of (E)-1-(2,4-difluoro-phenyl)-propane-1,2-dione-2-oxime (m.p. 99-101° C.) are obtained in 88.6% yield. the end of the addition the batch is formed stirred for a further hour The product is isolated by filtration the filter cake is washed with 75 g of methylcyclohexane at 0° C.

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

Procedure: To a solution of 1-(2,4-difluoro-phenyl)-propan-1-one (21.29 g, 125.1 mmol) in toluene (120 mL) was added sodium acetate (26.75 g, 326.1 mmol) and cyclohexylhydrazine mesylate (34.0 g, 163 mmol). The reaction mixture was heated to reflux in a Dean-Stark apparatus for 12 hours. The reaction was cooled to room temperature and poured into 1N hydrochloric acid (100 mL). The toluene layer was separated and washed with water (75 mL) and brine (75 mL). The organic layer was dried over magnesium sulfate, filtered, and concentrated to yield 30.07 g of 1-cyclohexyl-3-ethyl-6-fluoro-1H-indazole (98% yield). 1H NMR (400 MHz, CDCl3) d 1.33 (t, 3, J=7.7), 1.35-1.44 (m, 2), 1.47-1.96 (m, 8), 2.93 (q, 2, J=7.7), 4.14-4.22 (m, 1), 6.81 (dt, 1, J=8.9, 2.1), 6.99 (dd, 1, J=9.8, 2.1), 7.40 (ddd, 1, J=8.7, 5.2, 0.4). 13C NMR (100 MHz, CDCl3) d 13.97, 20.53, 25.37, 25.84, 32.32, 58.18, 94.77 (d, J=27.4), 109.11 (d, J=26.0), 119.38, 121.75 (d, J=11.5), 139.89 (d, J=13.0), 146.61, 161.95 (d, J=242). IR 2968, 2934, 2856, 1624, 1507, 1174, 1125, 825 cm-1. Analysis calculated for C15H19FN2 : C, 73.14; H, 7.77; N, 11.37. Found: C, 73.33; H, 7.90; N, 11.46. The reaction mixture was heated to reflux in a Dean-Stark apparatus for 12 hours The toluene layer was separated washed with water (75 mL) and brine (75 mL) The organic layer was dried over magnesium sulfate filtered concentrated

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

Procedure: To a solution of 1-(2,4-difluoro-phenyl)-propan-1-one (21.29 g, 125.1 mmol) in toluene (120 mL) was added sodium acetate (26.75 g, 326.1 mmol) and cyclohexylhydrazine mesylate (34.0 g, 163 mmol). The reaction mixture was heated to reflux in a Dean-Stark apparatus for 12 hours. The reaction was cooled to room temperature and poured into 1N hydrochloric acid (100 mL). The toluene layer was separated and washed with water (75 mL) and brine (75 mL). The organic layer was dried over magnesium sulfate, filtered, and concentrated to yield 30.07 g of 1-cyclohexyl-3-ethyl-6-fluoro-1H-indazole (98% yield). 1H NMR (400 MHz, CDCl3) d 1.33 (t, 3, J=7.7), 1.35-1.44 (m, 2), 1.47-1.96 (m, 8), 2.93 (q, 2, J=7.7), 4.14-4.22 (m, 1), 6.81 (dt, 1, J=8.9, 2.1), 6.99 (dd, 1, J=9.8, 2.1), 7.40 (ddd, 1, J=8.7, 5.2, 0.4). 13C NMR (100 MHz, CDCl3) d 13.97, 20.53, 25.37, 25.84, 32.32, 58.18, 94.77 (d, J=27.4), 109.11 (d, J=26.0), 119.38, 121.75 (d, J=11.5), 139.89 (d, J=13.0), 146.61, 161.95 (d, J=242). IR 2968, 2934, 2856, 1624, 1507, 1174, 1125, 825 cm-1. Analysis calculated for C15H19FN2 : C, 73.14; H, 7.77; N, 11.37. Found: C, 73.33; H, 7.90; N, 11.46. The reaction mixture was heated to reflux in a Dean-Stark apparatus for 12 hours The toluene layer was separated washed with water (75 mL) and brine (75 mL) The organic layer was dried over magnesium sulfate filtered concentrated

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 1-(2,4-difluoro-phenyl)-propan-1-one (21.29 g, 125.1 mmol) in toluene (120 mL) was added sodium acetate (26.75 g, 326.1 mmol) and cyclohexylhydrazine mesylate (34.0 g, 163 mmol). The reaction mixture was heated to reflux in a Dean-Stark apparatus for 12 hours. The reaction was cooled to room temperature and poured into 1N hydrochloric acid (100 mL). The toluene layer was separated and washed with water (75 mL) and brine (75 mL). The organic layer was dried over magnesium sulfate, filtered, and concentrated to yield 30.07 g of 1-cyclohexyl-3-ethyl-6-fluoro-1H-indazole (98% yield). 1H NMR (400 MHz, CDCl3) d 1.33 (t, 3, J=7.7), 1.35-1.44 (m, 2), 1.47-1.96 (m, 8), 2.93 (q, 2, J=7.7) 4.14-4.22 (m, 1), 6.81 (dt, 1, J=8.9, 2.1), 6.99 (dd, 1, J=9.8, 2.1), 7.40 (ddd, 1, J=8.7, 5.2, 0.4). 13C NMR (100 MHz, CDCl3) d 13.97, 20.53, 25.37, 25.84, 32.32, 58.18, 94.77 (d, J=27.4), 109.11 (d, J=26.0), 119.38, 121.75 (d, J=11.5), 139.89 (d, J=13.0), 146.61, 161.95 (d, J=242). IR2968, 2934, 2856, 1624, 1507, 1174, 1125, 825 cm−1. Analysis calculated for C15H19FN2: C, 73.14; H, 7.77; N, 11.37. Found: C, 73.33; H, 7.90; N, 11.46. The reaction mixture was heated to reflux in a Dean-Stark apparatus for 12 hours The toluene layer was separated washed with water (75 mL) and brine (75 mL) The organic layer was dried over magnesium sulfate filtered concentrated

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

Procedure: A 19 g portion of 2,4-difluoropropiophenone was dissolved in 150 ml of tetrahydrofuran. With cooling in a dry ice-acetone bath and spending 20 minutes or more, to this was added dropwise 112 ml of 1N tetrahydrofuran solution of lithium hexamethyl disilazide. After 1 hour of stirring at the same temperature, to this was further added dropwise 50 ml of tetrahydrofuran solution containing 14 g of 4-cyanobenzyl bromide spending 20 minutes or more, followed by overnight stirring at room temperature. The reaction solution was mixed with saturated ammonium chloride aqueous solution, poured into water and then extracted with ethyl acetate. The thus obtained organic layer was washed with water and dried on anhydrous magnesium sulfate. After removing the solvent by evaporation under a reduced pressure, the resulting residue was purified by a silica gel column chromatography (ethyl acetate:n-hexane=1:9) to obtain 13 g of 2',4'-difluoro-2-methyl-3-(4-cyanophenyl)-propiophenone with a yield of 41%. With cooling in a dry ice-acetone bath spending 20 minutes or more followed by overnight stirring at room temperature extracted with ethyl acetate The thus obtained organic layer was washed with water dried on anhydrous magnesium sulfate After removing the solvent by evaporation under a reduced pressure the resulting residue was purified by a silica gel column chromatography (ethyl acetate:n-hexane=1:9)

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

Procedure: In methylene chloride (300 ml) was dissolved 2',4'-difluoropropiophenone (55 g), to which was added bromine (50 g) dropwise, while stirring, during 30 minutes. The mixture was stirred for 30 minutes at room temperature. To the reaction mixture was added water (200 ml), and the methylene chloride layer was washed three times, followed by drying over anhydrous magnesium sulfate. The solvent was distilled off to leave 2-bromo-2',4'-difluoropropiophenone (77 g) as a pale yellow oily product. The mixture was stirred for 30 minutes at room temperature the methylene chloride layer was washed three times by drying over anhydrous magnesium sulfate The solvent was distilled off

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

Procedure: To a mixture of m-difluorobenzene (100 ml) and anhydrous aluminium chloride (114 g) was added dropwise, while stirring, propionyl chloride (66 ml), during 45 minutes. The mixture was then stirred for 2 hours on an oil bath of 50°-55° C. The reaction mixture was cooled, to which was added methylene chloride (300 ml). The resultant solution was added by portions to ice-water (11) while stirring. Methylene chloride layer was separated, and the aqueous layer was subjected to extraction twice with methylene chloride (60 ml). Methylene chloride layers were combined and washed with water (200 ml), followed by drying over anhydrous magnesium sulfate. The solvent was distilled off to leave 2',4'-difluoropropiophenone (111.4 g) as a pale yellow oily product. 1H-NMR (CDCl3) δ: 1.17~1.24(3H), 2.92~3.05(2H), 6.82~7.02(2H), 7.89~8.03(1H) was added dropwise The mixture was then stirred for 2 hours on an oil bath of 50°-55° C The reaction mixture was cooled, to which while stirring Methylene chloride layer was separated the aqueous layer was subjected to extraction twice with methylene chloride (60 ml) washed with water (200 ml) by drying over anhydrous magnesium sulfate The solvent was distilled off

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

Procedure: To a solution of 1-(2,4-difluoro-phenyl)-propan-1-one (21.29 g, 125.1 mmol) in toluene (120 mL) was added sodium acetate (26.75 g, 326.1 mmol) and cyclohexylhydrazine mesylate (34.0 g, 163 mmol). The reaction mixture was heated to reflux in a Dean-Stark apparatus for 12 hours. The reaction was cooled to room temperature and poured into 1 N hydrochloric acid (100 mL). The toluene layer was separated and washed with water (75 mL) and brine (75 mL). The organic layer was dried over magnesium sulfate, filtered, and concentrated to yield 30.07 g of 1-cyclohexyl-3-ethyl-6-fluoro-1H-indazole (98% yield). 1H NMR (400 MHz, CDCl3) d 1.33 (t, 3, J=7.7), 1.35-1.44 (m, 2), 1.47-1.96 (m, 8), 2.93 (q, 2, J=7.7), 4.14-4.22 (m, 1), 6.81 (dt, 1, J=8.9, 2.1), 6.99 (dd, 1, J=9.8, 2.1), 7.40 (ddd, 1, J=8.7, 5.2, 0.4). 13C NMR (100 MHz, CDCl3) d 13.97, 20.53, 25.37, 25.84, 32.32, 58.18, 94.77 (d, J=27.4), 109.11 (d, J=26.0), 119.38, 121.75 (d, J=11.5), 139.89 (d, J=13.0), 146.61, 161.95 (d, J=242). The reaction mixture was heated to reflux in a Dean-Stark apparatus for 12 hours The toluene layer was separated washed with water (75 mL) and brine (75 mL) The organic layer was dried over magnesium sulfate filtered concentrated