Sodium Hydroxide → 4-(1,4-dimethyl-1H-pyrazol-5-yl)-5-ethyl-2-thiophenecarboxylic acid

Participants

Reaction Steps

A solution of methyl 4-(1,4-dimethyl-1H-pyrazol-5-yl)-5-ethyl-2-thiophenecarboxylate (488 mg, 1.85 mmol) in 6N sodium hydroxide (3.08 ml, 18.5 mmol) and Tetrahydrofuran (10 ml) was stirred at 70° C. in a sealed tube for 1 h. The resulting solution was cooled and then partitioned between H2O-DCM. The aqueous phase was adjusted to pH ˜4 and then washed several times with DCM. The combined organic fractions were dried over Na2SO4 and concentrated affording the title compound as a yellow foam (448 mg, 1.79 mmol, 96% yield) as a yellow oil: LCMS (ES) m/e 251 (M+H)+.

Provenance & Evidence