2,3-Difluorophenetole

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:; See reaction.notes.procedure_details.

Procedure: Mixture of 20.0 g (79.3 mmol) of 4-ethoxy-2,3-difluoroiodobenzene [obtained by lithiating 4-ethoxy-2,3-difluorobenzene with sec-butyl lithium and then reacting with iodine], 18.9 g (118.9 mmol) of dihydroxy(3-fluorophenyl)borane [obtained by reacting a Grignard reagent, which was prepared from 3-fluorobromobenzene and magnesium, with trimethoxyborane and then hydrolyzing with hydrochloric acid], 21.9 g (158.6 mmol) of K2CO3, 2.0 g of 5% Pd—C, and 100 ml of mixed solvent of toluene/ethanol/ water (1/1/1) was heated to reflux for 13 hours. Subsequently, after the catalyst was filtered off, the mixture was subjected to extraction with toluene, and the organic layer thus obtained was washed with water thrice and then dried over anhydrous magnesium sulfate. The solvent was distilled off under a reduced pressure and the residue thus obtained was subjected to silica gel column chromatography (eluent: heptane/toluene=8/2) to obtain 17.3 g of a crude 4-ethoxy-2,3,3′-trifluorobiphenyl. (Yield: 86.2%) obtained obtained was heated to reflux for 13 hours Subsequently, after the catalyst was filtered off the mixture was subjected to extraction with toluene the organic layer thus obtained was washed with water thrice dried over anhydrous magnesium sulfate The solvent was distilled off under a reduced pressure the residue thus obtained

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:; See reaction.notes.procedure_details.

Procedure: To a solution of 5-bromo-2-chlorobenzoyl chloride 21d (3.41 g, 13.4 mmol) and 1-ethoxy-2,3-difluoro-benzene 23b (2.42 g, 15.2 mmol) in dichloromethane (50 mL) was added anhydrous aluminium chloride (1.82 g, 13.7 mmol) in portions over 1 hours at 0° C. The mixture was stirred at room temperature for 16 hours. The reaction mixture was quenched with hydrochloric acid (10 mL, 2 M) and extracted with dichloromethane (40 mL×4). The combined layers were dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated in vacuo to give the title compound 23d as yellow oil (5.03 g, 100%). This material was not further purified. The reaction mixture was quenched with hydrochloric acid (10 mL, 2 M) extracted with dichloromethane (40 mL×4) The combined layers were dried over anhydrous sodium sulfate filtered The filtrate was concentrated in vacuo

Conditions: temp:70.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 2,3-difluorophenol 21a (2.04 g, 14.5 mmol) in acetone (50 mL) were added methyl iodide (1.62 mL, 9.98 mmol) and potassium carbonate (3.18 g, 23.06 mmol) in turn at room temperature. The mixture was warmed up to 70° C. and stirred for 3 hours, and then filtered. To the mixture was added ethyl acetate (40 mL). The resulting mixture was washed with water (40 mL×2), dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated in vacuo to give the title compound 23b as yellow oil (2.42g, 100%). This material was not further purified. The compound was characterized by the following spectroscopic data: 1H NMR (400 MHz, CDCl3) δ (ppm): 7.01-6.95 (m, 1H), 6.80-6.72 (m, 2H), 4.14 (q, 2H), 1.48 (t, 3H). filtered To the mixture was added ethyl acetate (40 mL) The resulting mixture was washed with water (40 mL×2) dried over anhydrous sodium sulfate filtered The filtrate was concentrated in vacuo

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

Procedure: A solution of 54.5 ml of 1-bromopentane in 200 ml of THF was added dropwise to 10.7 g of magnesium turnings under a layer of 100 ml of THF, and the mixture was subsequently refluxed for 1 hour. A solution of 104.5 g of 4-(4-ethoxy-2,3-difluorophenyl)cyclohexanone (obtainable by lithiation of 4-ethoxy-2,3-difluorobenzene using n-butyllithium, reaction with 1,4-dioxaspiro[4.5]decan-8-one, dehydration and hydrogenation of the resultant alkene, followed by removal of the carbonyl protecting group under acidic conditions) in 500 ml of THF was then added dropwise at 40° C., and the mixture was refluxed for 2 hours. Conventional work-up gave 4-(4-ethoxy-2,3-difluoro-phenyl)-1-pentylcyclohexanol. the mixture was subsequently refluxed for 1 hour followed by removal of the carbonyl protecting group under acidic conditions) in 500 ml of THF was then added dropwise at 40° C. the mixture was refluxed for 2 hours

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

Procedure: A solution of 54.5 ml of 1-bromopentane in 200 ml of THF was added dropwise to 10.7 g of magnesium turnings under a layer of 100 ml of THF, and the mixture was subsequently refluxed for 1 hour. A solution of 104.5 g of 4-(4-ethoxy-2,3-difluorophenyl)cyclohexanone (obtainable by lithiation of 4-ethoxy-2,3-difluorobenzene using n-butyllithium, reaction with 1,4-dioxaspiro[4.5]decan-8-one, dehydration and hydrogenation of the resultant alkene, followed by removal of the carbonyl protecting group under acidic conditions) in 500 ml of THF was then added dropwise at 40° C., and the mixture was refluxed for 2 hours. Conventional work-up gave 4-(4-ethoxy-2,3-difluoro-phenyl)-1-pentylcyclohexanol. the mixture was subsequently refluxed for 1 hour followed by removal of the carbonyl protecting group under acidic conditions) in 500 ml of THF was then added dropwise at 40° C. the mixture was refluxed for 2 hours

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

Procedure: A solution of 54.5 ml of 1-bromopentane in 200 ml of THF was added dropwise to 10.7 g of magnesium turnings under a layer of 100 ml of THF, and the mixture was subsequently refluxed for 1 hour. A solution of 104.5 g of 4-(4-ethoxy-2,3-difluorophenyl)cyclohexanone (obtainable by lithiation of 4-ethoxy-2,3-difluorobenzene using n-butyllithium, reaction with 1,4-dioxaspiro[4.5]decan-8-one, dehydration and hydrogenation of the resultant alkene, followed by removal of the carbonyl protecting group under acidic conditions) in 500 ml of THF was then added dropwise at 40° C., and the mixture was refluxed for 2 hours. Conventional work-up gave 4-(4-ethoxy-2,3-difluorophenyl)-1-pentylcyclohexanol. the mixture was subsequently refluxed for 1 hour followed by removal of the carbonyl protecting group under acidic conditions) in 500 ml of THF was then added dropwise at 40° C. the mixture was refluxed for 2 hours