Methanol → Methyl 3-(chloromethyl)-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxylate

Participants

Reaction Conditions

Reaction Steps

1-(3-chloropyridin-2-yl)-3-(hydroxymethyl)-1H-pyrazole-5-carboxylic acid hydrochloride (0.1 mol) was initially charged in 100 ml of toluene. 24 g of SOCl2 were added in portions at 60° C. The mixture was heated at 70° C. for 3 h, in the course of which the precipitate went completely into the solution. Methanol (30 ml) was slowly added dropwise to the mixture and the solution was stirred at 30° C. for a further 1 h. Subsequently, the solution was concentrated under reduced pressure. This gave 95% of the product with a purity of 96%.

Provenance & Evidence