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 dissolved 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/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-a93134a112fa49c2bf24e03c4b58438e

Quelldatensatz

uspto-grants-2014_04

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08691836B2