DL-leucine → 2-Bromo-4-methylpentanoic acid

HRID 636754Notes

Reaction equation

HRID 636754 reaction equation
N[CH:2]([C:7]([OH:9])=[O:8])[CH2:3][CH:4]([CH3:6])[CH3:5].[Br-:10].[K+].N([O-])=O.[Na+].ClCCl>S(=O)(=O)(O)O>[Br:10][CH:2]([CH2:3][CH:4]([CH3:6])[CH3:5])[C:7]([OH:9])=[O:8]

Participants

6

Reactant 4

HCID 857DL-leucineHCID 6344DichloromethaneHCID 253877Potassium BromideHCID 23668193Sodium Nitrite

Product 1

HCID 1426812-Bromo-4-methylpentanoic acidYield 85.5%

Reagents, catalysts & solvents 1

HCID 1118Sulfuric AcidSolvent

Procedure

D,L-Leucine (50 g, 0.38 mol) and potassium bromide (158.7 g, 1.33 mol) were dissolved in aqueous sulfuric acid (from 75 mL of H2SO4 and 250 mL of water), and sodium nitrite (34.8 g, 0.5 mol) was added portionwise wile keeping the temperature below −1° C. The mixture was kept at 0° C. for 1 h, then dichloromethane was added under stirring. The dichlomethane layer was collected and the aqueous phase was extracted twice with further portions of dichloromethane. The combined dichloromethane extracts were dried (Na2SO4) and evaporated to give the title compound as a pale yellow oil (63.4 g, 0.32 mol; 85.5%).

Workup

  1. customthe temperature below −1° C
  2. customThe dichlomethane layer was collected
  3. extractionthe aqueous phase was extracted twice with further portions of dichloromethane
  4. dry with materialThe combined dichloromethane extracts were dried (Na2SO4)
  5. customevaporated

Sources & evidence

ORD record
ord-0868e1b44d0c4fdaaf4c27986a12c601
Source dataset
uspto-grants-2001_02
Patent number
US06194451B1

Reaction notes

Loading…