Hydrogen Bromide → (R)-2-Bromo-3-phenylpropionic acid

HRID 260333

Reaction equation

HRID 260333 reaction equation
N[C@@H:2]([C:10]([OH:12])=[O:11])[CH2:3][C:4]1[CH:9]=[CH:8][CH:7]=[CH:6][CH:5]=1.[BrH:13].N([O-])=O.[Na+]>O>[C:4]1([CH2:3][C@@H:2]([Br:13])[C:10]([OH:12])=[O:11])[CH:9]=[CH:8][CH:7]=[CH:6][CH:5]=1

Participants

5

Reactant 3

HCID 260Hydrogen BromideHCID 71567D-PhenylalanineHCID 23668193Sodium Nitrite

Product 1

HCID 11746403(R)-2-Bromo-3-phenylpropionic acidYield 43.3%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
-5 °C

Procedure

Mix D-phenylalanine (186.4 g, 1.128 mol) and 49% hydrobromic acid (372.8 g), cool to -5° C. and add, by dropwise addition, a solution of sodium nitrite (77.9 g) in water (565 mL) over a period of about 1 hour (vigorous gas evolution). Stir at -5° C. to 0° C. for 4 hours, extract into ethyl ether (3×1 L), dry (MgSO4) and evaporate the solvent in vacuo. Purify by chromatography (5% acetic aci/95% methylene chloride) and distillation to give 3-phenyl-2(R)-bromopropionic acid (112 g, 43%); bp 128°-135° C. @ 0.25 torr.

Workup

  1. additionadd, by dropwise addition
  2. extractionextract into ethyl ether (3×1 L)
  3. dry with materialdry (MgSO4)
  4. customevaporate the solvent in vacuo
  5. distillationPurify by chromatography (5% acetic aci/95% methylene chloride) and distillation

Sources & evidence

ORD record
ord-049237c9c8c44b0ba190e641951fb4cd
Source dataset
uspto-grants-1996_06
Patent number
US05527795

Linked notes

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