Hydrogen Bromide → (2R,3S)-2-Bromo-3-methylpentanoic acid

HRID 132986Notes

Reaction equation

HRID 132986 reaction equation
N[C@H:2]([C@@H:6]([CH3:9])[CH2:7][CH3:8])[C:3]([OH:5])=[O:4].[BrH:10].N([O-])=O.[Na+]>O>[Br:10][C@H:2]([C@@H:6]([CH3:9])[CH2:7][CH3:8])[C:3]([OH:5])=[O:4]

Participants

5

Reactant 3

HCID 260Hydrogen BromideHCID 94206D-AlloisoleucineHCID 23668193Sodium Nitrite

Product 1

HCID 51381013(2R,3S)-2-Bromo-3-methylpentanoic acidYield 87.5%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent2×

Procedure

The (2R,3S)-2-amino-3-methylpentanoic acid (D-allo-isoleucine, 1g, 7.62 mmol) was dissolved in a mixture of HBr 48% (6.95 mL, 61 mmol) and H2O (10.5 mL). At 0° C., a solution of NaNO2 (1.68 g, 24.4 mmol) in H2O (5 mL) was added over a period of 30 min. The reaction was stirred for two hours. The reaction mixture was degassed in vacuo and extracted with EtOAc (2×20mL). The extracts were washed with water (15 mL), dried (Na2SO4), filtered and evaporated to give 1.3 g (87% yield) of the (2R, 3S)-2-bromo-3-methylpentanoic acid as a light yellow oil.

Workup

  1. customThe reaction mixture was degassed in vacuo
  2. extractionextracted with EtOAc (2×20mL)
  3. washThe extracts were washed with water (15 mL)
  4. dry with materialdried (Na2SO4)
  5. filtrationfiltered
  6. customevaporated

Sources & evidence

ORD record
ord-20ad5afcb6474824bde3777d88952182
Source dataset
uspto-grants-2008_06
Patent number
US07390789B2

Reaction notes

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