Pyridine → 4-chloro-6-[2-(3-chloro-pyridin-2-yl)-5-trifluoromethyl-2H-pyrazol-3-yl]-7-oxa-2-thia-1,3,5-triaza-cyclopenta[b]naphthalen-8-one

Participants

Reaction Steps

To a suspension of 300 mg (1.31 mmol) of 6-amino-7-chloro-benzo[1,2,5]thiadiazole-5-carboxylic acid in 12 ml of acetonitrile, is added 381 mg (1.31 mmol) of 2-(3-chloro-pyridin-2-yl)-5-trifluoromethyl-2H-pyrazole-3-carboxylic acid followed by 0.47 ml (5.88 mmol) of pyridine. The mixture is stirred at ambient temperature during 30 min. Then the suspension is cooled at a temperature of 0° C. and 0.36 ml (4.57 mmol) of methanesulfonyl chloride is added dropwise. The mixture is stirred at a temperature of 0° C. during 30 min and 2 hours at ambient temperature. Then the solvent is evaporated and the residue is precipitated in a minimum of cold H2O. After filtration and washing of the solid with a minimum of cold H2O, 585 mg (1.21 mmol, 92%) of a dark violet solid is obtained. LC/MS: 485/487 (M+1)+.

Provenance & Evidence