Hydrochloric Acid → 4-Bromo-2-(4,5-dihydroisoxazol-3-yl)-3-methylbenzenesulfonyl chloride

Participants

Reaction Conditions

Reaction Steps

At 15° C., a solution of 9 g (35 mmol) of 4-bromo-2-(4,5-dihydro-isoxazol-3-yl)-3-methylaniline in 50 ml of glacial acetic acid is added to 15 ml of conc. hydrochloric acid. At 5-10° C., a solution of 2.44 g (35 mmol) of sodium nitrite in 10 ml of water is then added dropwise, and the mixture is stirred at 5° C. for 1 hour. This solution is then added dropwise at room temperature to a mixture of a solution of 47 g (0.74 mol) of sulfur dioxide in 100 ml of glacial acetic acid and a solution of 2.23 g (13 mmol) of copper(II) chloride in 5 ml of water. The mixture is stirred at room temperature for 1 hour and then poured onto 300 ml of ice-water and extracted with methylene chloride. The organic phase is washed with water, dried with magnesium sulfate and concentrated.

Provenance & Evidence