Pyrazole → 6-(6-chloro-pyrimidine-4-carbonyl)-3-methyl-4-pyrazol-1-ylmethyl-3H-benzoxazol-2-one

Participants

Reaction Steps

Under a nitrogen atmosphere 0.15 g (0.49 mmol) 6-(6-chloropyrimidine-4-carbonyl)-3,4-dimethyl-3H-benzoxazol-2-one, 95 mg (0.53 mmol) N-bromosuccinimide and 5.0 mg (30 mmol) 2,2′-azobis-isobutyronitrile (AIBN) in 15 mL carbon tetrachloride were combined and refluxed for 4 h. The precipitate formed was filtered off and the filtrate was combined with 20 μL isopropanol. After brief stirring 36 mg (0.53 mmol) pyrazole and 0.17 mL (0.99 mmol) DIPEA were added and the mixture was refluxed for 6 h. Then the reaction mixture was filtered through silica gel and washed with DCM/EtOAc (1/1). The filtrate was evaporated down i. vac. and the residue was reacted further as the crude product.

Provenance & Evidence