Acetic Acid → 5-Fluoro-6-[(tetrahydro-4H-pyran-3-yl)propylamino]benzoxazolin-2-one

Participants

Reaction Steps

To a solution of 6-amino-5-fluoro-benzoxazolin-2-one (2.1 g, 12.5 mmole) in methanol (80 ml) were added 3-(tetrahydro-2H-pyran-3-yl) propanal (1.95 g, 13.7 mmole) and acetic acid (1 ml) at room temperature, and then the mixture was stirred for 1 hour. Sodium cyanoborohydride (0.867 g, 13.7 mmole) was combined and stirring continued for 17 hours at room temperature. The reaction mixture was concentrated in vacuo, and the residue was treated with aqueous ammonium chloride solution. The organic substance was extracted with ethyl acetate/tetrahydrofuran. The extracts were washed with brine, dried over magnesium sulfate, and concentrated to afford crude product. This crude product was recrystallized from methanol to give 1.40 g of the title compound: m.p. 144°-145° C.

Provenance & Evidence