反应详情

温度

-78 °C

A 100 mL round bottom flask equipped with magnetic stir bar was charged with 1.22 g of benzyl 3-chlorosulfonyl-2(R)-methylpropionate in 15 mL CH2Cl2 and cooled to −78° C. To this solution was added to 10 mL of liquid ammonia at −78° C. After 20 minutes the reaction was warmed to room temperature, concentrated in vacuo to afford a white solid. The solid was slurried in ethyl acetate, filtered to remove inorganic salts and concentrated in vacuo to afford 1.08 g of benzyl 3-aminosulfonyl-2(R)-methylpropionate as a clear yellow oil. The crude product was used without further purification. Part B: 3-aminosulfonyl-2(R)-methylpropionic acid A 100 mL Fisher/Porter vessel was charged with 1.1 g of crude benzyl 3-aminosulfonyl-2(R)-methylpropionate in 35 mL MeOH and a catalytic amount of 10% Pd—C. The mixture was hydrogenated at 50 psi for 24 hours, filtered through Celite and concentrated in vacuo to yield 700 mg of 3-aminosulfonyl-2(R)-methylpropionic acid as a clear oil. The crude acid was used without further purification.

1. customA 100 mL round bottom flask equipped with magnetic stir bar
2. temperatureAfter 20 minutes the reaction was warmed to room temperature
3. concentrationconcentrated in vacuo
4. customto afford a white solid
5. filtrationfiltered
6. customto remove inorganic salts
7. concentrationconcentrated in vacuo