Ethanol → Ethyl 3-methylthiophene-2-carboxylate

To a stirred solution of 3-methylthiophene-2-carboxylic acid (5.00 g, 35.17 mmol) in ethanol (50 mL) was added thionyl chloride (2.60 mL, 35.62 mmol). The resulting reaction mixture was stirred at reflux for 16 h, and allowed to cool to ambient temperature and concentrated in vacuo. The residue was dissolved in ethyl acetate (200 mL) and washed with saturated aqueous sodium bicarbonate solution (3×100 mL) and brine (100 mL). The organic layer was dried over sodium sulfate, filtered and concentrated in vacuo to afford ethyl 3-methylthiophene-2-carboxylate as light yellow liquid (5.96 g, 99%): 1H NMR (300 MHz, CDCl3) δ 7.37 (d, J=5.0 Hz, 1H), 6.91 (d, J=5.0 Hz, 1H), 4.33 (q, J=7.1 Hz, 2H), 2.55 (s, 3H), 1.37 (t, J=7.1 Hz, 3H).

1. customThe resulting reaction mixture
2. temperatureat reflux for 16 h
3. concentrationconcentrated in vacuo
4. dissolutionThe residue was dissolved in ethyl acetate (200 mL)
5. washwashed with saturated aqueous sodium bicarbonate solution (3×100 mL) and brine (100 mL)
6. dry with materialThe organic layer was dried over sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated in vacuo

ORD record

ord-4cddbfcd0ef649778be051be287eb81a

Source dataset

uspto-grants-2012_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08258160B2