1,3-Dibromo-5,5-dimethylhydantoin → HCID 86723274, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of 4-(4-fluorophenyl)-7-isopropyl-7H-imidazo[4,5-c]pyridazine (Preparation 86, 770 mg, 3.00 mmol) in concentrated sulfuric acid (7.00 mL) at 0° C. was added 1,3-dibromo-5,5-dimethyl hydantoin (687 mg, 2.40 mmol) portionwise over 1.5 hours and the reaction stirred at 0° C. for 1 hour. The reaction mixture was added dropwise into a solution of saturated aqueous sodium thiosulfate solution (20 mL) at 0° C. Following complete addition the reaction mixture was basified to pH=9 with solid potassium carbonate. The reaction mixture was filtered through celite, washed with CH2Cl2 (20 mL) and extracted into CH2Cl2 (3×40 mL), dried over Na2SO4, filtered and concentrated under vacuum to yield a pale yellow solid. Purification by silica gel column chromatography eluting with EtOAc:CH2Cl2 1:1 afforded the title compound as a pale yellow solid (558 mg, 55%).

Provenance & Evidence