Toluene → 3-Anilino-4-isopropoxycarbonyl-5-methylpyrazole

Participants

Reaction Steps

35.7 g of isopropyl 2-chloroacetate is added to a suspension of 33.5 g of 4-phenylthiosemicarbazide in 150 ml of tetrahydrofuran. After the mixture has been stirred for 30 minutes it is boiled for a further 30 minutes and then allowed to cool. The precipitated solid is isolated by suction filtering, washed with acetone and the residue is heated in a water/acetone mixture (1:1). After the separated sulfur has been poured off, the whole is allowed to cool and is neutralised with aqueous NaHCO3, solution and the precipated solid is isolated; m.p. 138°-139° C. (from toluene).

Provenance & Evidence