Boron tribromide → (1R,2S)-2-(4-Hydroxyphenyl)-N-(2-hydroxy-1-phenylethyl)cyclopropanecarboxamide

To a 250 mL RB flask fitted with magnetic stirrer was charged with 100 mL of dichloromethane. To the stirred solvent was added (1R,2S)—N-(2-hydroxy-1-phenylethyl)-2-(4-methoxyphenyl)cyclopropanecarboxamide (1.9 g, 6 mmol). The reaction mixture was brought to 0° C. and boron tribromide (0.86 mL, 9 mmol) was added drop wise. The reaction mixture was allowed to stir at room temperature for 45 minutes. The reaction mixture was quenched with ethanol (5 mL), the reaction mixture was concentrated to distill off the solvent; water (25 mL) was added and extracted with ethyl acetate (25 mL). The organic layer was washed with saturated NaHCO3 solution (10 mL) and brine solution (10 mL). The organic layer was dried over Na2SO4 and the solvent was removed under reduced pressure. The product was obtained as white solid (0.55 g, yield: 58.7%). 1H NMR (300 MHz, DMSO-d6): δ 9.20 (s, 1H), 8.47-8.50 (d, 1H), 7.21-7.30 (m, 5H), 6.88-6.91 (d, 2H), 6.63-6.66 (d, 2H), 4.86-4.90 (t, 2H), 3.52-3.56 (t, 2H), 2.05-2.11 (m, 1H), 1.87-1.93 (m, 1H), 1.24-1.29 (m, 1H), 1.04-1.10 (m, 1H).

1. customTo a 250 mL RB flask fitted with magnetic stirrer
2. customwas brought to 0° C.
3. customThe reaction mixture was quenched with ethanol (5 mL)
4. concentrationthe reaction mixture was concentrated
5. distillationto distill off the solvent
6. additionwater (25 mL) was added
7. extractionextracted with ethyl acetate (25 mL)
8. washThe organic layer was washed with saturated NaHCO3 solution (10 mL) and brine solution (10 mL)
9. dry with materialThe organic layer was dried over Na2SO4
10. customthe solvent was removed under reduced pressure

ORD record

ord-d9ac6ec353a14743ab1d9a10cb2bada5

Source dataset

uspto-grants-2016_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09278915B2