Hydrogen Bromide → (R)-Methyl 2-bromo-2-phenylacetate

Temperatur

0 °C

(S)-methyl 2-amino-2-phenylacetate (5 g, 24.8 mmol, 1 equiv) was dwassolved in a mixture of 48% hydrogen bromide (13 ml, 198 mmol, 8 equiv) and water (19 ml). An aqueous solution of sodium nitrite (5.48 g, 79.36 mmol, 3.2 equiv) was added slowly and the mixture stirred at 0° C. for 1.5 h. The reaction was degassed in vacuo and extracted with ether. The organic layer was further washed with water and brine, dried over MgSO4, and concentrated in vacuo. The resulting residue was purified using the Biotage flash chromatography system (SNAP 100 g cartridge, Rf=0.5, gradient—1%-10% ethyl acetate in hexanes) to afford the (R)-methyl 2-bromo-2-phenylacetate as a light yellow oil (2.3 g, 40% yield); 1H NMR (400 MHz, DMSO-d6): δ 3.72 (s, 3H); 5.95 (s, 1H); 7.36-7.42 (m, 3H); 7.54 (d, 2H, J=1.6 Hz); 7.56 (d, 1H, J=2 Hz); MS for C9H9BrO2 m/z 229.98 (M+H)+.

1. customThe reaction was degassed in vacuo
2. extractionextracted with ether
3. washThe organic layer was further washed with water and brine
4. dry with materialdried over MgSO4
5. concentrationconcentrated in vacuo
6. customThe resulting residue was purified

ORD-Eintrag

ord-72810b0b6bce4894a9337d2f41441f8a

Quelldatensatz

uspto-grants-2015_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US09156840B2