Methanol → Methyl 1-benzothiophene-3-carboxylate

Participants

Reaction Steps

To a methanol (500 mL) solution of 1-benzothiophene-3-carbaldehyde (51.3 g, 300 mmol), sodium cyanide (22.0 g, 449 mmol) was added thereto at room temperature. Then, manganese dioxide (89.0 g, 901 mmol) was added at 0° C. The reaction mixture was stirred for 20 hours at room temperature, and then the reaction liquor was filtered. The filtrate was concentrated under reduced pressure. To the obtained residue, diethyl ether (200 mL), a saturated aqueous solution of sodium hydrogen carbonate (150 mL) and water (150 mL) were added, and the mixture was partitioned. The aqueous layer was extracted with diethyl ether (200 mL), and the organic layer was combined, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The obtained residue was purified by column chromatography using silica gel (silica gel 300 g, hexane:diethyl ether=100:0 to 85:15), to obtain the title compound (52.1 g, 90%) as a transparent oily matter.

Provenance & Evidence