Boron tribromide → Ethyl 3-(2-fluoro-4-hydroxyphenyl)propanoate

Temperature

0 °C

To a 25 mL RB flask fitted with magnetic stirrer was charged with 10 mL of dichloromethane. To the stirred solvent was added ethyl 3-(2-fluoro-4-methoxyphenyl)propanoate (0.45 g, 2 mmol). The reaction mixture was cooled to 0° C. and boron tribromide (0.45 mL) was added drop wise. After stirred for 30 minutes, the reaction mixture was quenched with ethanol (1 mL) at 0° C. by slow addition. The reaction mixture was concentrated to distill off the solvent; ethyl acetate (10 mL) was added. The organic layer was washed with saturated NaHCO3 solution (10 mL), followed by brine solution (10 mL). The organic layer was dried over anhydrous Na2SO4 and the solvent was removed under reduced pressure. The product was obtained as colorless oil (0.421 g, yield: 99.75%). 1H NMR (300 MHz, CDCl3): δ 6.93-6.99 (t, 1H), 6.43-6.48 (m, 2H), 5.54 (s, 1H), 4.02-4.09 (q, 2H), 2.79-2.85 (t, 2H), 2.50-2.55 (t, 2H), 1.14-1.19 (t, 3H).

1. customTo a 25 mL RB flask fitted with magnetic stirrer
2. customthe reaction mixture was quenched with ethanol (1 mL) at 0° C. by slow addition
3. concentrationThe reaction mixture was concentrated
4. distillationto distill off the solvent
5. additionethyl acetate (10 mL) was added
6. washThe organic layer was washed with saturated NaHCO3 solution (10 mL)
7. dry with materialThe organic layer was dried over anhydrous Na2SO4
8. customthe solvent was removed under reduced pressure

ORD record

ord-f74da54bc0694ec3957228dfa50af036

Source dataset

uspto-grants-2016_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09278915B2