Hydrochloric Acid → 4-Thiazolidinecarboxylic acid, methyl ester

Temperature

0 °C

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.

1. concentrationconcentrated carefully under reduced pressure
2. customThe obtained residue was dried in vacuo overnight
3. customto give a white solid, which
4. stirringThe resulting suspension was stirred at RT for 30 min
5. filtrationfiltered
6. concentrationThe filtrate was concentrated carefully under reduced pressure
7. customto give a colorless oil

ORD record

ord-78af3367829e452ea289a9d47f2137d7

Source dataset

uspto-grants-2003_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06670386B2