3215-64-3

151-50-8

2014-83-7

3215-64-3

Example 13-(2,6-dichloro-phenyl)-6-(2,4-difluoro-phenylamino)-1-diethyl-pyrazolo[1,5-a]pyrimidin-2-one was synthesized as follows: Step 1 (Synthesis of 2,6-dichlorophenylacetonitrile): a solution of potassium cyanide (26 g, 400.00 mmol) and 18-crown-6 (0.05 g) in water (60 mL) was added to a 500 mL round bottom flask. Subsequently, an ethanol (300 mL) solution of 2,6-dichlorobenzyl chloride (40 g, 206.24 mmol) was added to this solution. The reaction mixture was stirred under reflux conditions for 1 to 3 hours and the progress of the reaction was monitored by thin layer chromatography (TLC, unfolding agent ratio ethyl acetate: petroleum ether = 1:4). After completion of the reaction, the mixture was concentrated to dryness using a rotary evaporator. The concentrated residue was transferred to a dispensing funnel and washed with water (5 x 100 mL) to afford 35.4 g (95% yield) of 2-(2,6-dichlorophenyl)acetonitrile as a white solid. The product can be used directly in the next reaction without further purification.