1,1'-Carbonyldiimidazole → 8-bromo-1-(tetrahydro-2H-pyran-4-yl)-7-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[4,3-c]quinolin-4-one

Participants

Reaction Conditions

Reaction Steps

To a mixture of 3.23 g of 4-bromo-2-[1-(tetrahydro-2H-pyran-4-yl)-1H-pyrazol-5-yl]-5-(trifluoromethyl)aniline and 32 mL of N-methylpyrrolidone were added 2.6 mL of DIPEA and 1.8 g of CDI, followed by stirring at 150° C. for 1.5 hours. After ice-cooling, diisopropyl ether/ethyl acetate (4/1) and ice were added thereto, followed by stirring. The precipitated solid was collected by filtration, and washed with water and diisopropyl ether/ethyl acetate (4/1). The obtained solid was added to diisopropyl ether/ethyl acetate (4/1), and heated, followed by stirring at room temperature for 10 minutes, and the solid was collected by filtration, washed with diethyl ether, and then dried under reduced pressure to obtain 2.95 g of 8-bromo-1-(tetrahydro-2H-pyran-4-yl)-7-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[4,3-c]quinolin-4-one.

Provenance & Evidence