2-Aminophenol → 3,4-Dihydro-2H-1,4-benzoxazine

Participants

Reaction Conditions

Reaction Steps

To a suspension of 2-aminophenol (1.0 g, 9.2 mmol) and potassium carbonate (6.36 g, 46 mmol) in dry DMF (10 mL) was added 1,2-dibromoethane (2.59 g, 13.8 mmol). The mixture was then heated at 125° C. for 15 hours. After cooling, the mixture was treated with crushed ice and extracted with ethyl acetate. The organic extracts were dried over sodium sulfate and the solvent was removed under reduced pressure. The residue was purified by flash chromatography on silica gel using ethyl acetate/petroleum ether 1:10 (v:v) as eluent to give 3,4-dihydro-2H-benzo[b][1,4]oxazine as reddish oil (0.81 g, 65%). LC-MS (ES-API); rt 7.51 min; m/z calculated for C8H9NO [M+H]+ 136.1, found 136.1.

Provenance & Evidence