Potassium Hydroxide → 4-(1-methyl-1H-pyrazol-5-yl)-5-(trifluoromethyl)-2-thiophenecarboxylic Acid

To a solution of methyl 4-(1-methyl-1H-pyrazol-5-yl)-5-(trifluoromethyl)-2-thiophenecarboxylate (250 mg, 0.77 mmol), in THF/H2O (3 mL/0.3 mL), was added KOH (217 mg, 3.88 mmol). The reaction mixture was heated to 50° C. for 4 h. After the mixture was concentrated and diluted with H2O, the pH was adjusted to 3. The mixture was extracted with DCM (5 mL×3). The collected organic layers were concentrated under vacuum to give crude acid (235 mg, 80% pure) which was used directly in the next step without further purification: LC-MS (ES) 277 (M+H)+.

1. concentrationAfter the mixture was concentrated
2. additiondiluted with H2O
3. extractionThe mixture was extracted with DCM (5 mL×3)
4. concentrationThe collected organic layers were concentrated under vacuum

ORD-Eintrag

ord-a064036a969b4df1a1ecdcc13b807312

Quelldatensatz

uspto-grants-2013_04

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08410158B2