Methanol → Methyl 5-methyl-2-thiophenecarboxylate

To a solution of 5-methylthiophene-2-carboxylic acid (100 g, 703 mmol) in methanol (1.0 L) was added conc. sulfuric acid (10 ml) and the mixture was heated under reflux for 2 days. The reaction mixture was cooled to room temperature and concentrated under reduced pressure. Diethyl ether (1.0 L) was added to the residue. The mixture was washed successively with water (500 ml×4) and saturated brine (500 ml), and dried over magnesium sulfate. Filtration and concentration under reduced pressure gave methyl 5-methylthiophene-2-carboxylate (109 g, yield 100%).

1. temperaturethe mixture was heated
2. temperatureunder reflux for 2 days
3. concentrationconcentrated under reduced pressure
4. additionDiethyl ether (1.0 L) was added to the residue
5. washThe mixture was washed successively with water (500 ml×4) and saturated brine (500 ml)
6. dry with materialdried over magnesium sulfate
7. filtrationFiltration and concentration under reduced pressure

ORD record

ord-c6b0516750e24dcaa229e35217802e70

Source dataset

uspto-grants-2010_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07659263B2