Hydrochloric Acid → 4-Thiazolidinecarboxylic acid, methyl ester

Participants

Reaction Conditions

Reaction Steps

Hydrogen chloride gas was bubbled through a suspension of L-thioproline (990 mg, 7.55 mmol) in MeOH (30 mL) cooled at 0° C. for 5 min. The resulting clear solution was stirred at RT for 2 h, then concentrated carefully under reduced pressure. The obtained residue was dried in vacuo overnight to give a white solid, which was dissolved in MeOH (30 mL) and treated with Diaion® WA21J resin (6 g). The resulting suspension was stirred at RT for 30 min, then filtered. The filtrate was concentrated carefully under reduced pressure and the oily residue stripped with toluene (2×) to give a colorless oil.

Provenance & Evidence