(Diethylamino)sulfur trifluoride → (+/-)-10-[Fluoro-(4-fluoro-2-methoxy-phenyl)-methyl]-2-pyrimidin-4-yl-7,8,9,10-tetrahydro-6H-pyrimido[1,2-a]azepin-4-one

Participants

Reaction Steps

To a solution of 0.290 g (0.73 mmol) of (+/−)-10-[(4-fluoro-2-methoxy-phenyl)-hydroxy-methyl]-2-pyrimidin-4-yl-7,8,9,10-tetrahydro-6H-pyrimido[1,2-α]azepin-4-one (example 4) in dichloromethane (14 mL) under argon at −78° C. was added 0.294 g of diethylaminosulfur trifluoride (1.83 mmol) diluted in 5 ml of dichloromethane. The reaction was allowed to increase to room temperature. The reaction was stirred at room temperature for 2 h; the mixture was quenched at 0° C. with the addition of methanol and stirred overnight. A saturated solution of ammonium chloride was added and the mixture was extracted with dichloromethane. The organic phase was washed with a saturated solution of sodium chloride and dried over sodium sulfate and concentrated. The residue was purified by flash chromatography (dichloromethane with 2% of methanol and 0.2% of ammonia) to afford 0.072 g (25%) of a white solid as an isomer mixture (95/5).

Provenance & Evidence