Cesium carbonate → 5-Phenylthiophene-3-carboxylic acid

Participants

Reaction Steps

5-Bromo-thiophene-3-carboxylic acid (2.07 g, 10 mmol) was dissolved in dimethoxyethane (15 mL) and ethanol (15 mL). Phenyl boronic acid (14 mmol), [1,1′-bis(diphenylphosphino)ferrocine]dichloropalladium (II) (0.5 mmol) and caesium carbonate (14 mmol) were added and the reaction mixture refluxed under nitrogen overnight. The solvent was evaporated under vacuum, and the residue dissolved in ethyl acetate. The organic solution was washed with 1 N hydrochloric acid, dried over magnesium sulfate, filtered and the solvent evaporated. The residue was dissolved in hot ethyl acetate, filtered and the solvent evaporated to give the title compound as a pale brown solid. LCMS m/z 203.20 [M−H]− R.T.=3.23 min (Analytical Method 5).

Provenance & Evidence