Methyl iodide → 4-fluoro-3-methyl-6-nitro-1,3-benzoxazol-2(3H)-one

Participants

Reaction Conditions

Reaction Steps

Iodomethane (0.393 ml, 6.31 mmol) is added in portions to crude 4-fluoro-6-nitro-1,3-benzoxazol-2(3H)-one (Step 5, 1.00 g, 5.05 mmol) and 1,8-diazabicyclo[5.4.0]undec-7-ene (0.94 ml, 6.31 mmol) in DMF (10 ml). The reaction is stirred at 65° C. overnight, diluted with ethyl acetate, washed with 2N HCl and saline, dried (MgSO4), and evaporated to give crude product containing trace amounts of undesired 5-nitro isomer. Purification by flash column chromatography (20% ethyl acetate/hexane) gives pure product as a white solid (0.89 g, 83%); mp 118-9° C.

Provenance & Evidence