Dimethylformamide → 6-Bromo-2,2,7-trimethyl-4H-benzo[1,4]oxazin-3-one

Participants

Reaction Steps

A solution of Compound 1A (4.24 g, 22.2 mmol) in 150 mL of chloroform was treated with 5 mL of dry DMF followed by 4.4 g (24.4 mmol) of NBS at room temperature. After 4 hours, the reaction was quenched with 150 mL of a saturated sodium thiosulfate solution. The aqueous layer was extracted with chloroform and the combined organic layers were dried with magnesium sulfate, filtered, and excess solvent removed on the rotary evaporator. The crude product was purified via silica gel chromatography (5% EtOAc/Hexanes) to yield 3.48 g of brominated product (58%). MS (electrospray): mass calculated for C11H12BrNO2, 269.01; m/z found 268, [M+H]+.

Provenance & Evidence