Dimethylformamide → 1-(5-trifluoromethylpyridin-2-yl)-5-methyl-1H-pyrazole-4-carboxamide

Participants

Reaction Conditions

Reaction Steps

To a suspension of 5-methyl-1-[5-(trifluoromethyl)pyridin-2-yl]-1H-pyrazole-4-carboxylic acid (3.0 g) described in Reference Example 8 in toluene (37 ml) were added N,N-dimethylformamide (catalytic amount) and thionyl chloride (2.2 ml), stirred at 80° C. for 8.5 hours, and then the solvent was evaporated in vacuo. To a solution of the residue in pyridine (20 ml) was added a solution of 4-(5-aminopyridin-2-yl)piperidine-1-carboxylic acid tert-butyl ester (2.8 g) in pyridine (17 ml), stirred at 80° C. for 5 hours, then additionally, 5-methyl-1-[5-(trifluoromethyl)pyridin-2-yl]-1H-pyrazole-4-carboxylic acid chloride (980 mg) described in Reference Example 180 was added thereto, and stirred at 80° C. for 2 hours. To the reaction solution was added triethylamine (4.2 ml), then water was added thereto, and the precipitated solid was washed with water and ethyl acetate to give N-[6-O-tert-butyloxycarbonylpiperidin-4-yl)pyridin-3-yl]-5-methyl-1-[5-(trifluoromethyl)pyridin-2-yl]-1H-pyrazole-4-carboxamide (4.0 g) as a yellow solid.

Provenance & Evidence