5-Benzyl 3-methyl 1-(p-fluorophenyl)-4-isopropyl-1H-pyrazole-3,5-dicarboxylate → 1-(4-fluoro-phenyl)-4-isopropyl-1 H-pyrazole-3,5-dicarboxylic acid 3-methyl ester

Participants

Reaction Conditions

Reaction Steps

To a solution of 1-(4-fluoro-phenyl)-4-isopropyl-1H-pyrazole-3,5-dicarboxylic acid 5-benzyl ester 3-methyl ester (18.95 g, 47.8 mmol) in MeOH (300 mL) at 25° C. under N2 was added 10% Pd—C (700 mg; commercially available from Sigma Aldrich). The reaction vessel was evacuated and filled with H2 and then stirred at 25° C. for 3 hrs. Subsequently, the reaction vessel was flushed with N2 and filtered through a pad of celite. The filtrate was concentrated to afford 1-(4-fluoro-phenyl)-4-isopropyl-1H-pyrazole-3,5-dicarboxylic acid 3-methyl ester (14.6g, 99%) in sufficient purity for use in the next step: H-NMR (CDCl3) δ 7.36-7.31 (m, 2 H), 7.11-7.06 (m, 2 H), 3.90 (s, 3 H), 3.86-3.82 (m, 1 H), 1.43 (d, 6 H).

Provenance & Evidence