Potassium → (S)-3-cyano-5-methylhexanoic acid

HRID 2181396Notes

Reaction equation

HRID 2181396 reaction equation
[K].[C:2]([C:4](=[CH:9][CH:10]([CH3:12])[CH3:11])[CH2:5][C:6]([OH:8])=[O:7])#[N:3]>CO>[C:2]([C@@H:4]([CH2:9][CH:10]([CH3:12])[CH3:11])[CH2:5][C:6]([OH:8])=[O:7])#[N:3]

Participants

4

Reactant 2

HCID 5462222PotassiumHCID 53432669HCID 53432669, compound

Product 1

HCID 9855540(S)-3-cyano-5-methylhexanoic acid

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Conditions

Temperature
45 °C

Procedure

A glass liner is charged with the potassium salt of 3-cyano-5-methylhex-3-enoic acid (from Example 1B) and methanol and placed in a 600 mL PARR hydrogenation vessel. The vessel is purged with nitrogen and then with hydrogen via charging to 60 psi and stirring for 10 minutes to ensure thorough equilibration of gases and releasing of the pressure on five cycles. The vessel is heated to 45° C., and a solution of [(R,R)-MeDuPHOS]Rh(COD)BF4− in deoxygenated methanol (11 mg in 10 mL) is added via syringe. The vessel is again purged with hydrogen and then pressurized to 60 psi with stirring. Periodically, hydrogen is added to maintain the pressure between 50 to 65 psi. Hydrogen uptake ceases after 120 minutes. After 2 hours, the mixture is cooled to room temperature, the pressure is released, and the solvent is removed to give the crude product. A small sample is removed and acidified with 1 N HCl to give (S)-3-cyano-5-methylhexanoic acid. GC analysis shows >99% conversion with 96.7% e.e S isomer.

Workup

  1. customThe vessel is purged with nitrogen
  2. additiona solution of [(R,R)-MeDuPHOS]Rh(COD)BF4− in deoxygenated methanol (11 mg in 10 mL) is added via syringe
  3. customThe vessel is again purged with hydrogen
  4. stirringwith stirring
  5. additionPeriodically, hydrogen is added
  6. temperatureto maintain the pressure between 50 to 65 psi
  7. waitHydrogen uptake ceases after 120 minutes
  8. waitAfter 2 hours
  9. temperaturethe mixture is cooled to room temperature
  10. customthe solvent is removed
  11. customto give the crude product
  12. customA small sample is removed

Sources & evidence

ORD record
ord-69b11b3fe7034da785541124cbad39a4
Source dataset
uspto-grants-2005_05
Patent number
US06891059B2

Reaction notes

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