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

Participants

Reaction Steps

10.0 g (47.8 mmol) of the compound from Example 42A and 8.3 g (57.3 mmol) of the compound from Example 7A are initially introduced into 100 ml ethanol and 1.5 ml (2.2 g, 19.0 mmol) TFA are added. The mixture is stirred under reflux for 12 h. The crystals which have precipitated out are filtered off, the residue on the filter is rinsed with ethanol and the intermediate product is dried overnight in vacuo. This is then suspended in 20 ml methanol, 100 ml of a 4 M solution of hydrogen chloride in dioxane are added and the mixture is subsequently stirred at RT for 1 h. The solid is filtered off, the residue on the filter is washed with dioxane, ethyl acetate and diisopropyl ether and the product is dried in vacuo.

Provenance & Evidence