Potassium Carbonate → methyl (R)-2-acetylamino-3-(4-amino-3-chloro-5-methyl-phenyl)-propionate

Participants

Reaction Conditions

Reaction Steps

22 mL Alcalase 2.4 L FG (Novozymes ANS; DK 2880 Bagsvaerd) were added to a solution of 27.3 g (178 mmol) disodium hydrogen phosphate dihydrate in 1000 mL water at 37° C. and the pH was adjusted to 7.5 by the addition of sodium dihydrogen phosphate dihydrate. Then 21.1 g (74 mmol) methyl 2-acetylamino-3-(4-amino-3-chloro-5-methyl-phenyl)-propionate dissolved in 210 mL acetone was added dropwise with stirring at 37° C. The pH of the reaction mixture was kept constantly in the range from pH 7.4 to pH 7.6 by the addition of 1 M NaOH. After the addition had ended the mixture was stirred for 3 h at 37° C. The reaction mixture was combined with 500 ml 15% potassium carbonate solution and extracted twice with 250 ml dichloromethane. The combined organic extracts were dried over sodium sulphate, evaporated down under reduced pressure and purified by column chromatography over silica gel.

Provenance & Evidence