Hydrochloric Acid → Amoxicillin

Participants

Reaction Steps

Meanwhile, 4-methylpentan-2-one (70 ml) was stirred and cooled to 0° and ethyl chloroformate (2.0 ml, 0.0208 mole) and a 1% solution of N-methylmorpholine in 4-methylpentan-2-one (3 ml) was added. The solution was cooled to -5° and sodium (R)-N-(1-methoxycarbonyl propen-2-yl)-α-amino-p-hydroxyphenylacetate (5.87 g, 0.02 mole) was added. The suspension was stirred at 0° to -5° for 30 minutes, cooled to -30° and then added to the solution of 6-APA prepared above. The mixture was stirred at -30° for 45 minutes when water (50 ml) was added. The stirred two-phase mixture was acidified to pH 1.1 with concentrated hydrochloric acid and stirred at 0° to 2° for 75 minutes, during which time a white precipitate separated. The mixture was adjusted to pH 5.2 with 10% aqueous potassium hydroxide solution, and the white suspension was stirred and cooled to 0° for 1 hour and filtered. The filter was washed with ice-cold water (20 ml) and ethyl acetate (20 ml), and the solid was air dried at 35° to give amoxycillin trihydrate (6.33 g, 75.5% th.), [α]D25 + 237° (c 0.9; 0.1 N HCl).

Provenance & Evidence