1213855-60-7

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

Procedure: Next, to a solution of (R)-3-(4-bromo-phenyl)-2-tert-butoxycarbonylamino-propionic acid methyl ester (1.0 g, 2.79 mmol) in DCM (20 mL) is added DIBAL-H (4.85 mL, 1.0M in DCM) slowly by using syringe pump at −78° C. After the addition is complete the reaction is quenched by adding EtOAc and the mixture is warmed to room temperature. Then a saturated sodium potassium tartaric acid is added and the mixture is and stirred at room temperature for 1 hour. The organic phase is separated and the aqueous layer is extracted with EtOAc. The combined organic layers were washed with brine, dried over MgSO4, filtered and concentrated to give [(R)-1-(4-bromo-benzyl)-2-oxo-ethyl]-carbamic acid tert-butyl ester which is used directly in the next reaction. at −78° C After the addition is quenched by adding EtOAc Then a saturated sodium potassium tartaric acid is added The organic phase is separated the aqueous layer is extracted with EtOAc The combined organic layers were washed with brine dried over MgSO4 filtered concentrated

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

Procedure: To a solution of (R)-3-(4-Bromo-phenyl)-2-tert-butoxycarbonylamino-propionic acid (1.0 g, 2.91 mmol) in DMF (5 mL) is added Cs2CO3 (1.041 g, 3.2 mmol) and the mixture is stirred at room temperature for 30 minutes. Then iodomethane (1.031 g, 7.26 mmol) is added and the mixture is stirred at room temperature about 72 hours. The pH is adjusted to 5˜6 by adding 1N HCl then the mixture is extracted with EtOAc. The combined organic layers were washed with water and brine, dried over MgSO4, filtered and concentrated to give (R)-3-(4-bromo-phenyl)-2-tert-butoxycarbonylamino-propionic acid methyl ester. HPLC Retention time 1.49 minutes (condition C): MS 358.3 (M−1). the mixture is stirred at room temperature about 72 hours the mixture is extracted with EtOAc The combined organic layers were washed with water and brine dried over MgSO4 filtered concentrated

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

Procedure: To a solution of (R)-3-(4-Bromo-phenyl)-2-tert-butoxycarbonylamino-propionic acid (1.0 g, 2.91 mmol) in DMF (5 mL) is added Cs2CO3 (1.041 g, 3.2 mmol) and the mixture is stirred at room temperature for 30 minutes. Then iodomethane (1.031 g, 7.26 mmol) is added and the mixture is stirred at room temperature about 72 hours. The pH is adjusted to 5˜6 by adding 1N HCl then the mixture is extracted with EtOAc. The combined organic layers were washed with water and brine, dried over MgSO4, filtered and concentrated to give (R)-3-(4-bromo-phenyl)-2-tert-butoxycarbonylamino-propionic acid methyl ester. HPLC Retention time 1.49 minutes (condition C): MS 358.3 (M−1). the mixture is stirred at room temperature about 72 hours the mixture is extracted with EtOAc The combined organic layers were washed with water and brine dried over MgSO4 filtered concentrated

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

Procedure: Next, to a solution of (R)-3-(4-bromo-phenyl)-2-tert-butoxycarbonylamino-propionic acid methyl ester (1.0 g, 2.79 mmol) in DCM (20 mL) is added DIBAL-H (4.85 mL, 1.0M in DCM) slowly by using syringe pump at −78° C. After the addition is complete the reaction is quenched by adding EtOAc and the mixture is warmed to room temperature. Then a saturated sodium potassium tartaric acid is added and the mixture is and stirred at room temperature for 1 hour. The organic phase is separated and the aqueous layer is extracted with EtOAc. The combined organic layers were washed with brine, dried over MgSO4, filtered and concentrated to give [(R)-1-(4-bromo-benzyl)-2-oxo-ethyl]-carbamic acid tert-butyl ester which is used directly in the next reaction. at −78° C After the addition is quenched by adding EtOAc Then a saturated sodium potassium tartaric acid is added The organic phase is separated the aqueous layer is extracted with EtOAc The combined organic layers were washed with brine dried over MgSO4 filtered concentrated

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

Procedure: To a solution of (R)-3-(4-Bromo-phenyl)-2-tert-butoxycarbonylamino-propionic acid (1.0 g, 2.91 mmol) in DMF (5 mL) is added Cs2CO3 (1.041 g, 3.2 mmol) and the mixture is stirred at room temperature for 30 minutes. Then iodomethane (1.031 g, 7.26 mmol) is added and the mixture is stirred at room temperature about 72 hours. The pH is adjusted to 5˜6 by adding 1N HCl then the mixture is extracted with EtOAc. The combined organic layers were washed with water and brine, dried over MgSO4, filtered and concentrated to give (R)-3-(4-bromo-phenyl)-2-tert-butoxycarbonylamino-propionic acid methyl ester. HPLC Retention time 1.49 minutes (condition C): MS 358.3 (M−1). the mixture is stirred at room temperature about 72 hours the mixture is extracted with EtOAc The combined organic layers were washed with water and brine dried over MgSO4 filtered concentrated