Sodium Hydroxide → 4-(4-ethyl-1-methyl-1H-pyrazol-5-yl)-5-methyl-2-thiophenecarboxylic acid
Reaction equation
[CH2:1]([C:3]1[CH:4]=[N:5][N:6]([CH3:18])[C:7]=1[C:8]1[CH:9]=[C:10]([C:14]([O:16]C)=[O:15])[S:11][C:12]=1[CH3:13])[CH3:2].[OH-].[Na+]>O1CCCC1>[CH2:1]([C:3]1[CH:4]=[N:5][N:6]([CH3:18])[C:7]=1[C:8]1[CH:9]=[C:10]([C:14]([OH:16])=[O:15])[S:11][C:12]=1[CH3:13])[CH3:2]Participants
4
Procedure
A solution of methyl 4-(4-ethyl-1-methyl-1H-pyrazol-5-yl)-5-methyl-2-thiophenecarboxylate (145 mg, 0.55 mmol) in 6N sodium hydroxide (1.8 ml, 10.97 mmol) and tetrahydrofuran (4.8 ml) was stirred at 60° C. in a sealed tube for 12 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 4-(4-ethyl-1-methyl-1H-pyrazol-5-yl)-5-methyl-2-thiophenecarboxylic acid (137 mg, 0.55 mmol, 100% yield) as a yellow oil: LCMS (ES) m/e 250 (M+H)+.