methyl 2,3-difluorobenzoate

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: Methyl 3-fluoro-2-(2-fluoro-6-methoxyphenoxy)benzoate (0.88 g, 60%) was prepared from methyl 2,3-difluorobenzoate (0.86 g, 5 mmol) and 2-fluoro-6-methoxyphenol (0.78 g, 5.5 mmol) as described in procedure A. Hydrolysis of this ester with LiOH in aqueous methanol furnished 2-(2-methoxy-6-fluorophenoxy)-3-fluorobenzoic acid (0.86 g, 90%). To a solution of 3-fluoro-2-(2-fluoro-6-methoxyphenoxy)benzoic acid (0.56 g, 2.0 mmol) in 1,2-dichloroethane (10 ml) was added oxalyl chloride (0.18 ml, 2.2 mmol). The solution was stirred at room temperature for 45 min. To this solution was added NaN3 (390 mg, 6 mmol) and the mixture was heated to reflux for 3 h. 2-Aminothiazole (200 mg, 2 mmol) was then added to this mixture and was further refluxed for 3 h. The mixture was concentrated and the residue was purified by column chromatography (silica, CH2Cl2 then 10% ethyl acetate in CH2Cl2) to afford 1-[3-fluoro-2-(2-fluoro-6-methoxyphenoxy)phenyl]-3-(thiazol-2-yl)urea in (414 mg, 55%).

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

Procedure: Methyl 3-fluoro-2-(2-fluoro-6-methoxyphenoxy)benzoate (0.88 g, 60%) was prepared from methyl 2,3-difluorobenzoate (0.86 g, 5 mmol) and 2-fluoro-6-methoxyphenol (0.78 g, 5.5 mmol) as described in procedure A. Hydrolysis of this ester with LiOH in aqueous methanol furnished 2-(2-methoxy-6-fluorophenoxy)-3-fluorobenzoic acid (0.86 g, 90%). To a solution of 3-fluoro-2-(2-fluoro-6-methoxyphenoxy)benzoic acid (0.56 g, 2.0 mmol) in 1,2-dichloroethane (10 ml) was added oxalyl chloride (0.18 ml, 2.2 mmol). The solution was stirred at room temperature for 45 min. To this solution was added NaN3 (390 mg, 6 mmol) and the mixture was heated to reflux for 3 h. 2-Aminothiazole (200 mg, 2 mmol) was then added to this mixture and was further refluxed for 3 h. The mixture was concentrated and the residue was purified by column chromatography (silica, CH2Cl2 then 10% ethyl acetate in CH2Cl2) to afford 1-[3-fluoro-2-(2-fluoro-6-methoxyphenoxy)phenyl]-3-(thiazol-2-yl)urea in (414 mg, 55%).

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

Procedure: Methyl 3-fluoro-2-(2-fluoro-6-methoxyphenoxy)benzoate (0.88 g, 60%) was prepared from methyl 2,3-difluorobenzoate (0.86 g, 5 mmol) and 2-fluoro-6-methoxyphenol (0.78 g, 5.5 mmol) as described in procedure A. Hydrolysis of this ester with LiOH in aqueous methanol furnished 2-(2-methoxy-6-fluorophenoxy)-3-fluorobenzoic acid (0.86 g, 90%). To a solution of 3-fluoro-2-(2-fluoro-6-methoxyphenoxy)benzoic acid (0.56 g, 2.0 mmol) in 1,2-dichloroethane (10 ml) was added oxalyl chloride (0.18 ml, 2.2 mmol). The solution was stirred at room temperature for 45 min. To this solution was added NaN3 (390 mg, 6 mmol) and the mixture was heated to reflux for 3 h. 2-Aminothiazole (200 mg, 2 mmol) was then added to this mixture and was further refluxed for 3 h. The mixture was concentrated and the residue was purified by column chromatography (silica, CH2Cl2 then 10% ethyl acetate in CH2Cl2) to afford 1-[3-fluoro-2-(2-fluoro-6-methoxyphenoxy)phenyl]-3-(thiazol-2-yl)urea in (414 mg, 55%).

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

Procedure: Methyl 3-fluoro-2-(2-fluoro-6-methoxyphenoxy)benzoate (0.88 g, 60%) was prepared from methyl 2,3-difluorobenzoate (0.86 g, 5 mmol) and 2-fluoro-6-methoxyphenol (0.78 g, 5.5 mmol) as described in procedure A. Hydrolysis of this ester with LiOH in aqueous methanol furnished 2-(2-methoxy-6-fluorophenoxy)-3-fluorobenzoic acid (0.86 g, 90%). To a solution of 3-fluoro-2-(2-fluoro-6-methoxyphenoxy)benzoic acid (0.56 g, 2.0 mmol) in 1,2-dichloroethane (10 ml) was added oxalyl chloride (0.18 ml, 2.2 mmol). The solution was stirred at room temperature for 45 min. To this solution was added NaN3 (390 mg, 6 mmol) and the mixture was heated to reflux for 3 h. 2-Aminothiazole (200 mg, 2 mmol) was then added to this mixture and was further refluxed for 3 h. The mixture was concentrated and the residue was purified by column chromatography (silica, CH2Cl2 then 10% ethyl acetate in CH2Cl2) to afford 1-[3-fluoro-2-(2-fluoro-6-methoxyphenoxy)phenyl]-3-(thiazol-2-yl)urea in (414 mg, 55%).

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: Methyl 3-fluoro-2-(2-fluoro-6-methoxyphenoxy)benzoate (0.88 g, 60%) was prepared from methyl 2,3-difluorobenzoate (0.86 g, 5 mmol) and 2-fluoro-6-methoxyphenol (0.78 g, 5.5 mmol) as described in procedure A. Hydrolysis of this ester with LiOH in aqueous methanol furnished 2-(2-methoxy-6-fluorophenoxy)-3-fluorobenzoic acid (0.86 g, 90%). To a solution of 3-fluoro-2-(2-fluoro-6-methoxyphenoxy)benzoic acid (0.56 g, 2.0 mmol) in 1,2-dichloroethane (10 ml) was added oxalyl chloride (0.18 ml, 2.2 mmol). The solution was stirred at room temperature for 45 min. To this solution was added NaN3 (390 mg, 6 mmol) and the mixture was heated to reflux for 3 h. 2-Aminothiazole (200 mg, 2 mmol) was then added to this mixture and was further refluxed for 3 h. The mixture was concentrated and the residue was purified by column chromatography (silica, CH2Cl2 then 10% ethyl acetate in CH2Cl2) to afford 1-[3-fluoro-2-(2-fluoro-6-methoxyphenoxy)phenyl]-3-(thiazol-2-yl)urea in (414 mg, 55%).

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

Procedure: Methyl 3-fluoro-2-(2-fluoro-6-methoxyphenoxy)benzoate (0.88 g, 60%) was prepared from methyl 2,3-difluorobenzoate (0.86 g, 5 mmol) and 2-fluoro-6-methoxyphenol (0.78 g, 5.5 mmol) as described in procedure A. Hydrolysis of this ester with LiOH in aqueous methanol furnished 2-(2-methoxy-6-fluorophenoxy)-3-fluorobenzoic acid (0.86 g, 90%). To a solution of 3-fluoro-2-(2-fluoro-6-methoxyphenoxy)benzoic acid (0.56 g, 2.0 mmol) in 1,2-dichloroethane (10 ml) was added oxalyl chloride (0.18 ml, 2.2 mmol). The solution was stirred at room temperature for 45 min. To this solution was added NaN3 (390 mg, 6 mmol) and the mixture was heated to reflux for 3 h. 2-Aminothiazole (200 mg, 2 mmol) was then added to this mixture and was further refluxed for 3 h. The mixture was concentrated and the residue was purified by column chromatography (silica, CH2Cl2 then 10% ethyl acetate in CH2Cl2) to afford 1-[3-fluoro-2-(2-fluoro-6-methoxyphenoxy)phenyl]-3-(thiazol-2-yl)urea in (414 mg, 55%).

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

Procedure: Methyl 3-fluoro-2-(2-fluoro-6-methoxyphenoxy)benzoate (0.88 g, 60%) was prepared from methyl 2,3-difluorobenzoate (0.86 g, 5 mmol) and 2-fluoro-6-methoxyphenol (0.78 g, 5.5 mmol) as described in procedure A. Hydrolysis of this ester with LiOH in aqueous methanol furnished 2-(2-methoxy-6-fluorophenoxy)-3-fluorobenzoic acid (0.86 g, 90%). To a solution of 3-fluoro-2-(2-fluoro-6-methoxyphenoxy)benzoic acid (0.56 g, 2.0 mmol) in 1,2-dichloroethane (10 ml) was added oxalyl chloride (0.18 ml, 2.2 mmol). The solution was stirred at room temperature for 45 min. To this solution was added NaN3 (390 mg, 6 mmol) and the mixture was heated to reflux for 3 h. 2-Aminothiazole (200 mg, 2 mmol) was then added to this mixture and was further refluxed for 3 h. The mixture was concentrated and the residue was purified by column chromatography (silica, CH2Cl2 then 10% ethyl acetate in CH2Cl2) to afford 1-[3-fluoro-2-(2-fluoro-6-methoxyphenoxy)phenyl]-3-(thiazol-2-yl)urea in (414 mg, 55%).

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

Procedure: To a solution of (1-benzenesulfonyl-1H-pyrrol-3-yl)-acetic acid (1.3 g, 4.90 mmol) in THF was added LiN(TMS)2 (12 mL, 1.0M in THF, 12 mmol) at −78° C. The resulting solution was stirred at this temperature for 1 hour and 0° C. for 1 hour and then was cooled to −78° C. again. To this solution was added 2,3-difluoro-benzoic acid methyl ester (1.1 g, 6.40 mmol) and the reaction was stirred at room temperature for 14 hours. The solution was poured into 2N HCl and extracted with EtOAc. The combined organic layers were dried over MgSO4, filtered, and evaporated. The crude product was purified by flash column eluting with 20% of EtOAc in hexanes to afford the title compound as a yellow oil (1.1 g, 58%). 1H NMR (500 MHz, CDCl3) δ7.77 (d, 2H), 7.50 (m, 2H), 7.42 (t, 2H), 7.28 (m, 1H), 7.05 (m, 3H), 6.18 (m, 1H), 3.98 (s, 2H) ppm. MS (ES+): m/e=362.1 (M+H); LC/Method A/3.98 min. was cooled to −78° C. again the reaction was stirred at room temperature for 14 hours extracted with EtOAc The combined organic layers were dried over MgSO4 filtered evaporated The crude product was purified by flash column eluting with 20% of EtOAc in hexanes