Trifluoroacetic acid → 5-(4-Fluorophenyl)-1-methyl-1H-pyrazole-3-carboxaldehyde

Participants

Reaction Steps

The compound from Step 1 (9 g) was treated with trifluoroacetic acid (30 mL) and water (30 mL). The trifluoacetic acid was removed in vacuo and the reaction mixture partitioned between ethyl acetate and saturated sodium bicarbonate. The organic layer was washed with saturated sodium bicarbonate (×2), brine and dried over MgSO4. The solvent was removed in vacuo to give a yellow oil which was crystallised from ethyl acetate/hexanes to give the title compound. 4.6 g 1H NMR (360, CDCl3) δ 9.97 (s, 1H), 7.38 (m, 2H), 7.20 (m, 2H), 6.80 (s, 1H), 3.95 (s, 3H).

Provenance & Evidence