Trifluoroacetic acid → 2-(6-Chloropyrimidin-4-yl)-4-(1H-1,2,3-triazol-1-yl)-1,2-dihydro-3H-pyrazol-3-one hydrochloride

Participants

Reaction Conditions

Reaction Steps

1.1 ml (1.6 g, 13.8 mmol) TFA are added to a mixture of 7.3 g (34.6 mmol) of the compound from Example 3A and 6.0 g (41.5 mmol) of the compound from Example 7A in 70 ml ethanol and the mixture is stirred at 100° C. for 20 h. The solid which has precipitated out is filtered off and the filtrate is concentrated in vacuo. The residue is suspended in 100 ml ethanol, 30 ml of a 30% strength sodium methanolate solution in methanol are added and the mixture is stirred at RT for 1.5 h. After addition of 42 ml of a 4 N solution of hydrogen chloride in dioxane (pH=5-6) and after stirring for 30 min, the solid is filtered off, washed first with ethanol and then with diethyl ether and dried in vacuo. Further purification is carried out by stirring in ethanol and acetonitrile several times. 10 ml of a 4 N solution of hydrogen chloride in dioxane are then added and the mixture is stirred at RT for 16 h. The product is filtered off, washed first with acetonitrile and then with diethyl ether and dried in vacuo.

Provenance & Evidence