Hydrochloric Acid → HCID 12000653, compound

Participants

Reaction Steps

The residue obtained from the evaporation of the mother liquor obtained from the crystallisation of (R)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4,5-dihydro-pyrazole-3-carboxylic acid with (+)-Cinchonine was treated with 6N HCl as described above for obtaining the free acid After evaporating the organic phase 23.63 g of a mixture with a theoretical composition of 13.34 mmoles of (R)-5-(4chlorophenyl)-1-(2,4-dichlorophenyl)-4,5-dihydro-pyrazole-3-carboxylic acid and 47.34 mmoles of (S)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4,5-dihydro-pyrazole-3-carboxylic acid were obtained. Said mixture, dissolved in 118 ml of acetone, was added on top of a solution of 18.7 g (47.4 mmoles) of brucine in 650 ml of acetone, stirred for a couple of minutes and left to crystallize at room temperature overnight. A creme-coloured solid was obtained that was filtered off and dried to yield 28 g (77.5% relative to the (S)-salt).

Provenance & Evidence