Pyridine → 3-Bromo-7-phenyl-hexahydroazepin-2-one

Participants

Reaction Conditions

Reaction Steps

To a 250 ml round-bottomed flask equipped with N2 inlet were added 5.12 g (24.6 mmol) phosphorus pentachloride and 45 ml methylene chloride. To the stirring mixture cooled to 0° C. was added dropwise over 20 minutes, a solution of 4.65 g (24.6 mmol) 7-phenyl-hexahydroazepin-2-one and 3.98 ml (49.2 mmol) pyridine in 40 ml methylene chloride. To the stirring mixture at 0° C. was then added 9.25 g (24.6 mmol) phenyltrimethylammonium bromide tribromide. The reaction was then allowed to warm to room temperature and stirred for 3 hours. It was then evaporated, taken up in tetrahydrofuran, quenched with water, evaporated, and partitioned between water and methylene chloride. The organic layer was washed with water and saturated aqueous sodium bisulfite, dried over sodium sulfate, and evaporated. The residue was chromatographed on silica gel with ethyl acetate/hexane as eluent to afford the product as an oil, 4.0 g (61%).

Provenance & Evidence