Isobutyl iodide → 7-fluoro4-isobutyl-2H-1,4-benzoxazin-3(4H)-one

To 3.96 g (99 mmol) of hexanes washed 60% sodium hydride in 150 ml of N,N-dimethylformamide was added portionwise as a solid 15 g (90 mmol) of 7-fluoro-2H-1,4-benzoxazin-3(4H)-one. When the addition was complete the reaction was stirred at room temperature for 10 min, after which time 19.8 g (108 mmol) of isobutyl iodide was added. The reaction was then stirred overnight before quenching into 200 ml of water. The aqueous phase was extracted with EtOAc (2×150 ml) and the combined organics were dried over Na2SO4, filtered and evaporated in vacuo to give the desired alkylated product, as a yellow oil (13 g, 65% yield).