Hydrochloric Acid → HCID 57642061, compound

Participants

Reaction Steps

A mixture of 1,2-dihydro-1-(1-methylethyl)-4-[(2-fluor-4-methoxyphenyl)-(ethoxy)methyl]-5-methyl-3H-pyrazol-3-one (294 g; 1.28 mol), methanol (4.5 L), aqueous hydrochloric acid (30%; 11 g) and water (80 mL) is hydrogenated with palladium on charcoal (10%-weight) (65 g) at 50° C. and 3 bar hydrogen pressure until hydrogen uptake ceases. THF (2.3 L) is added to the reaction mixture which is then filtered. The catalyst is washed with THF (1 L) and the solvent is distilled off under reduced pressure to a residual volume of approx. 700 to 800 ml. The resulting suspension is poured into water (1 L) with stirring. The precipitate is isolated by filtration, washed with water (400 ml) and dried at 55° C. to yield crystals (light beige).

Provenance & Evidence