Hydrochloric Acid → N-acetyl-4-mesyloxy-L-proline ethyl ester

Participants

Reaction Steps

457 g of methanesulfonyl chloride was added dropwise to a solution of 1020 g of N-acetyl-4-hydroxy-L-proline ethyl ester, 435 g of triethylamine and 1.9 L of chloroform at not higher than 15° C. while cooling. After stirring for 30 minutes, 1N hydrochloric acid (0.6 L) was added, and the layers were separated. The organic layer was washed with 5% aqueous sodium bicarbonate (600 g), washed with water (0.6 L), dried over magnesium sulfate, and concentrated under reduced pressure to obtain 802 g of N-acetyl-4-mesyloxy-L-proline ethyl ester as an oil.

Provenance & Evidence