Hydrochloric Acid → 4-Methyl-3-oxopentanoic acid

HRID 1988729Notes

Reaction equation

HRID 1988729 reaction equation
[C:1]([CH2:6][C:7]([O:9]CC)=[O:8])(=[O:5])[CH:2]([CH3:4])[CH3:3].Cl>[OH-].[Na+]>[C:1]([CH2:6][C:7]([OH:9])=[O:8])(=[O:5])[CH:2]([CH3:4])[CH3:3]

Participants

4

Reactant 2

HCID 313Hydrochloric AcidHCID 81583Ethyl isobutyrylacetate

Product 1

HCID 4400244-Methyl-3-oxopentanoic acid

Reagents, catalysts & solvents 1

HCID 14798Sodium HydroxideSolvent

Procedure

A mixture of ethyl isobutyrylacetate (20.47 g, 129 mmol) and 1.5 M aq NaOH (250 mL) is stirred at room temperature overnight. The solution is then cooled to 0° C. and acidified to pH 1-2 by the slow addition of conc. HCl (˜35 mL). The solution is then saturated with NaCl and extracted thrice with EtOAc and once with CHCl3. The combined extracts are dried over Na2SO4 and concentrated to 14.46 g (86%) of isobutyrylacetic acid as an oil. 1H NMR (CDCl3, 300 MHz) reveals a mixture of keto and enol forms (˜4:1), in favor of the keto form. Keto form: δ 3.57 (s, 2H), 2.73 (sept, J=6.9 Hz, 1H), 1.16 (d, J=6.9 Hz, 6H) ppm. Enol form: 11.85 (s, 1H), 5.03 (s, 1H), 2.44 (sept, J=6.9 Hz, 1H) 1.10 (d, J=6.9 Hz, 6H) ppm.

Workup

  1. temperatureThe solution is then cooled to 0° C.
  2. extractionsaturated with NaCl and extracted thrice with EtOAc
  3. dry with materialThe combined extracts are dried over Na2SO4
  4. concentrationconcentrated to 14.46 g (86%) of isobutyrylacetic acid as an oil
  5. additiona mixture of keto and enol forms (˜4:1)

Sources & evidence

ORD record
ord-dae3a2df20f9494584d4ca9dd9731c6c
Source dataset
uspto-grants-2010_01
Patent number
US07642267B2

Reaction notes

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