2-Thiophenecarboxaldehyde → HCID 66755625, compound

Participants

Reaction Steps

Sodium ethylate (41.4 g, 0.61 mol) was added under vigorous stirring to a solution of thiophene-2-carbaldehyde (57 g, 0.51 mol) and diethyl succinate (176 g, 1.01 mol) in ethanol (1 L). The reaction mixture was refluxed for 3 h and evaporated in vacuum (˜20 mmHg) at 50° C. until the solvent distillation ceased. The obtained residue was diluted with 500 mL of 10% HCl and 500 mL of ethyl acetate. The mixture was shaken. The organic layer was separated, diluted with 300 mL of a saturated aqueous solution of NaHCO3, and shaken. The aqueous layer was separated, neutralized by 10% HCl to pH 2, and subjected to extraction by 1 L of ethyl acetate. The organic layer was evaporated in vacuum (˜20 mmHg) at 60° C. and chromatographed on a layer of silica gel (300×150 mm) with hexane/ethyl acetate mixture, 1:1 as eluent. Fractions with the target product were collected and evaporated in vacuum to give 60 g (0.25 mol, 49%) of 3-(ethoxycarbonyl)-4-thien-2-ylbut-3-enoic acid as a light-brown oil.

Provenance & Evidence