Methanesulfonic Acid → HCID 14054310, compound

Participants

Reaction Conditions

Reaction Steps

5-Phenyl-3-(3-thienylmethylene)-2-furanone (44.7 g), methanesulfonic acid (220 cc) and glacial acetic acid (220 cc) are heated for 1 hour at 120° C. The mixture is cooled to 40° C., poured onto crushed ice and extracted with methylene chloride. The organic phase is washed with water and extracted with normal sodium hydroxide solution. The basic aqueous phase is washed with methylene chloride, acidified to pH 1 by adding an aqueous hydrochloric acid solution, and extracted with methylene chloride. The precipitate formed is filtered off and the organic phase is dried over magnesium sulfate and evaporated under reduced pressure. The evaporation residue and the precipitate are combined and stirred in ethyl acetate in the presence of silica gel (100 g). The silica is removed by filtration and the ethyl acetate evaporated under reduced pressure. This operation is repeated to produce 7-phenylbenzo[b]thiophene-5-carboxylic acid (29 g), m.p. 234° C.

Provenance & Evidence