Sulfuric Acid → Methyl alpha-hydroxy-alpha-2-thienyl-2-thiopheneacetate

Temperature

35 °C

2-Bromothiophene (9.68 mL, 0.1 mol) was slowly added to a stirred mixture of magnesium turnings (2.7 g, 0.11 mol) in diethyl ether (100 mL) under a nitrogen atmosphere at 0° C. The reaction mixture was stirred at 35° C. for 3 h and then dimethyl oxalate (5.9 g, 0.05 mol) in diethyl ether (150 mL) was added dropwise. The reaction mixture was heated at reflux (45° C.) for 45 min and then the mixture was allowed to cool to ambient temperature and 1.25 M sulfuric acid (150 mL) was added. The reaction mixture was stirred at ambient temperature for 1 h and then the organic layer was separated and washed with dilute aqueous sodium bicarbonate solution (100 mL), water (100 mL), dried with sodium sulfate, filtered and concentrated under reduced pressure. The resulting solid residue was recrystallized from tetrachloromethane (˜1 g/3 mL) to yield the title compound (7.68 g, 30 mmol, 60%).

1. temperatureThe reaction mixture was heated
2. temperatureat reflux (45° C.) for 45 min
3. temperatureto cool to ambient temperature
4. stirringThe reaction mixture was stirred at ambient temperature for 1 h
5. customthe organic layer was separated
6. washwashed with dilute aqueous sodium bicarbonate solution (100 mL), water (100 mL)
7. dry with materialdried with sodium sulfate
8. filtrationfiltered
9. concentrationconcentrated under reduced pressure
10. customThe resulting solid residue was recrystallized from tetrachloromethane (˜1 g/3 mL)

ORD record

ord-fc56e40c84a042a594536204f00ad687

Source dataset

uspto-grants-2011_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07893256B2