Boron tribromide → 5-Amino-4'-fluoro-7'-(2-fluoropyridin-3-yl)-2,6-dihydrospiro[[1,4]oxazine-3,9'-xanthen]-2'-ol

Participants

Reaction Conditions

Reaction Steps

To a suspension of 4′-fluoro-7′-(2-fluoropyridin-3-yl)-2′-methoxy-2,6-dihydrospiro[[1,4]oxazine-3,9′-xanthen]-5-amine (1.668 g, 4.07 mmol) in DCM (12 ml) was added boron tribromide (0.963 mL, 10.19 mmol) at 0° C. The reaction mixture was stirred for 45 hrs at 0° C. The reaction mixture was allowed to warm to RT and was stirred for additional 2 hrs. The reaction mixture was cooled to 0° C. and quenched by addition of saturated aqueous NaHCO3 solution (˜10 mL). The solvent was removed in vacuo, the mixture was diluted with water and filtered. The solid was washed with water and dried under reduced pressure to afford 5-amino-4′-fluoro-7′-(2-fluoropyridin-3-yl)-2,6-dihydrospiro[[1,4]oxazine-3,9′-xanthen]-2′-ol (1.53 g, 3.87 mmol, 95% yield).

Provenance & Evidence