Water → 5-(Trifluoromethyl)-1-benzothiophene-2-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of 10.0 g of methyl 5-(trifluoromethyl)benzo[b]thiophene-2-carboxylate, 1.80 g of lithium hydroxide monohydrate, 30 ml of water and 90 ml of methanol was stirred at 75° C. for 1 hour. The reaction mixture was cooled to room temperature and then concentrated under reduced pressure. To the obtained residue was added water, and washed with tert-butyl methyl ether 3 times. To the aqueous layer was added concentrated hydrochloric acid, and then extracted with tert-butyl methyl ether 3 times. The combined organic layer was washed with saturated aqueous sodium chloride solution, dried over magnesium sulfate, and then concentrated under reduced pressure to obtain 9.10 g of 5-(trifluoromethyl)benzo[b]thiophene-2-carboxylic acid.

Provenance & Evidence