methyl 4-amino-2,6-difluorobenzoate

Conditions: temp:90.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: At 60-70° C., 110 μl (0.46 mmol, 4 eq.) of T3P (50% in ethyl acetate) were added dropwise to a solution of 46 mg (0.13 mmol) of 2-[4-(5-chloro-2-cyanophenyl)-5-methoxy-2-oxopyridin-1(2H)-yl]butanoic acid (racemate) and 51 mg (0.27 mmol, 2 eq.) of methyl 4-amino-2,6-difluorobenzoate in 1 ml of pyridine. The reaction mixture was heated to 90° C., stirred at 90° C. for 30 min and cooled to RT, and water and ethyl acetate were added. After phase separation, the aqueous phase was extracted with ethyl acetate. The combined organic phases were washed with saturated aqueous sodium chloride solution, dried (sodium sulphate), filtered and concentrated under reduced pressure. The crude product was purified by normal phase chromatography (mobile phase: cyclohexane/ethyl acetate 10-50% mixtures). Yield: 54 mg (79% of theory) cooled to RT After phase separation the aqueous phase was extracted with ethyl acetate The combined organic phases were washed with saturated aqueous sodium chloride solution dried (sodium sulphate) filtered concentrated under reduced pressure The crude product was purified by normal phase chromatography (mobile phase: cyclohexane/ethyl acetate 10-50% mixtures)

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

Procedure: At RT, 0.5 ml of TFA was added to a solution of 36 mg (0.125 mmol) of methyl 4-[(tert-butoxycarbonyl)amino]-2,6-difluorobenzoate in 1 ml of dichloromethane, and the mixture was stirred at RT for 30 min. The reaction mixture was then concentrated under reduced pressure and the residue was co-evaporated repeatedly with dichloromethane and toluene and dried under reduced pressure. The crude product was used for the next step without purification. Yield: 24 mg (quant.) The reaction mixture was then concentrated under reduced pressure dried under reduced pressure The crude product was used for the next step without purification

Conditions: temp:90.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: At 60-70° C., 110 μl (0.46 mmol, 4 eq.) of T3P (50% in ethyl acetate) were added dropwise to a solution of 46 mg (0.13 mmol) of 2-[4-(5-chloro-2-cyanophenyl)-5-methoxy-2-oxopyridin-1(2H)-yl]butanoic acid (racemate) and 51 mg (0.27 mmol, 2 eq.) of methyl 4-amino-2,6-difluorobenzoate in 1 ml of pyridine. The reaction mixture was heated to 90° C., stirred at 90° C. for 30 min and cooled to RT, and water and ethyl acetate were added. After phase separation, the aqueous phase was extracted with ethyl acetate. The combined organic phases were washed with saturated aqueous sodium chloride solution, dried (sodium sulphate), filtered and concentrated under reduced pressure. The crude product was purified by normal phase chromatography (mobile phase: cyclohexane/ethyl acetate 10-50% mixtures). Yield: 54 mg (79% of theory) cooled to RT After phase separation the aqueous phase was extracted with ethyl acetate The combined organic phases were washed with saturated aqueous sodium chloride solution dried (sodium sulphate) filtered concentrated under reduced pressure The crude product was purified by normal phase chromatography (mobile phase: cyclohexane/ethyl acetate 10-50% mixtures)

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

Procedure: At RT, 0.5 ml of TFA was added to a solution of 36 mg (0.125 mmol) of methyl 4-[(tert-butoxycarbonyl)amino]-2,6-difluorobenzoate in 1 ml of dichloromethane, and the mixture was stirred at RT for 30 min. The reaction mixture was then concentrated under reduced pressure and the residue was co-evaporated repeatedly with dichloromethane and toluene and dried under reduced pressure. The crude product was used for the next step without purification. Yield: 24 mg (quant.) The reaction mixture was then concentrated under reduced pressure dried under reduced pressure The crude product was used for the next step without purification

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

Procedure: To a solution of 3-methoxymethoxy-5,5,8,8,-tetramethyl-5,6,7,8-tetrahydro-naphthalene-2-carboxylic acid (Compound K, as described in U.S. Pat. No. 5,856,490, 112mg, 0.38 mmol) in 6 ml of anhydrous methylene chloride was added 4-(dimethylamino)pyridine (DMAP, 100 mg, 0.46mmol), methyl 2,6-difluoro-4-aminobenzoate (Compound H1, as described in U.S. Pat. No. 5,856,490, 77mg, 0.38mmol ) and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC, 110 mg, 0.57 mmol). The reaction mixture was stirred at room temperature for overnight then concentrated to dryness. The residue was purified by column chromatography with ethyl acetate: hexane (1:9) to yield the title compound as a clear oil. then concentrated to dryness The residue was purified by column chromatography with ethyl acetate: hexane (1:9)

Conditions: temp:90.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: At 60-70° C., 110 μl (0.46 mmol, 4 eq.) of T3P (50% in ethyl acetate) were added dropwise to a solution of 46 mg (0.13 mmol) of 2-[4-(5-chloro-2-cyanophenyl)-5-methoxy-2-oxopyridin-1(2H)-yl]butanoic acid (racemate) and 51 mg (0.27 mmol, 2 eq.) of methyl 4-amino-2,6-difluorobenzoate in 1 ml of pyridine. The reaction mixture was heated to 90° C., stirred at 90° C. for 30 min and cooled to RT, and water and ethyl acetate were added. After phase separation, the aqueous phase was extracted with ethyl acetate. The combined organic phases were washed with saturated aqueous sodium chloride solution, dried (sodium sulphate), filtered and concentrated under reduced pressure. The crude product was purified by normal phase chromatography (mobile phase: cyclohexane/ethyl acetate 10-50% mixtures). Yield: 54 mg (79% of theory) cooled to RT After phase separation the aqueous phase was extracted with ethyl acetate The combined organic phases were washed with saturated aqueous sodium chloride solution dried (sodium sulphate) filtered concentrated under reduced pressure The crude product was purified by normal phase chromatography (mobile phase: cyclohexane/ethyl acetate 10-50% mixtures)

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

Procedure: At RT, 0.5 ml of TFA was added to a solution of 36 mg (0.125 mmol) of methyl 4-[(tert-butoxycarbonyl)amino]-2,6-difluorobenzoate in 1 ml of dichloromethane, and the mixture was stirred at RT for 30 min. The reaction mixture was then concentrated under reduced pressure and the residue was co-evaporated repeatedly with dichloromethane and toluene and dried under reduced pressure. The crude product was used for the next step without purification. Yield: 24 mg (quant.) The reaction mixture was then concentrated under reduced pressure dried under reduced pressure The crude product was used for the next step without purification