Step 2: To a solution of 2-(2-amino-4-bromophenyl)propan-2-ol (2.3 g, 10.0 mmol) in tetrahydrofuran (THF, 50 mL) was added N,N'-carbonyl diimidazole (CDI, 1.95 g, 12.0 mmol) at room temperature. The reaction mixture was slowly warmed to 60 °C and the reaction was stirred at this temperature overnight. After completion of the reaction, the solvent was removed by rotary evaporator. The residue was dissolved in ethyl acetate (50 mL) and washed sequentially with 1M aqueous hydrochloric acid (20 mL x 2) and saturated saline (20 mL x 2). The organic phase was dried with anhydrous sodium sulfate, filtered and concentrated. The resulting crude product was recrystallized by mixed solvent recrystallization of dichloromethane (DCM) and hexane to afford 7-bromo-4,4-dimethyl-1H-benzo[d][1,3]oxazin-2(4H)-one (2.3 g, 7.37% yield) as a white solid.
![7-bromo-4,4-dimethyl-1H-benzo[d][1,3]oxazin-2(4H)-one Structure](/CAS/GIF/1245643-21-3.gif)
