Ethyl Acetoacetate → Ethyl 2-acetyl-5,5-dimethyl-4-oxohexanoate

HRID 2417303Notes

Reaction equation

HRID 2417303 reaction equation
[C:1]([O:7][CH2:8][CH3:9])(=[O:6])[CH2:2][C:3]([CH3:5])=[O:4].[H-].[Na+].Br[CH2:13][C:14](=[O:19])[C:15]([CH3:18])([CH3:17])[CH3:16]>C1(C)C=CC=CC=1>[C:3]([CH:2]([CH2:13][C:14](=[O:19])[C:15]([CH3:18])([CH3:17])[CH3:16])[C:1]([O:7][CH2:8][CH3:9])=[O:6])(=[O:4])[CH3:5]

Participants

5

Reactant 3

HCID 8868Ethyl AcetoacetateHCID 21642BromopinacoloneHCID 24758Sodium hydride

Product 1

HCID 11775940Ethyl 2-acetyl-5,5-dimethyl-4-oxohexanoateYield 87.4%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent2×

Procedure

Ethyl acetoacetate (1 g, 7.68 mmol) was added dropwise to a suspension of NaH (60% in mineral oil, 338 mg, 8.45 mmol) in toluene (20 mL). The resulting suspension was stirred at rt for 10 min, then treated with 1-bromopinacolone (1.3 g, 7.32 mmol). The mixture was immersed in a 75° C. oil bath, and stirred under Ar for 1 h. The reaction was cooled to rt, diluted with toluene and washed with H2O (2×50 mL). The organic layer was dried over Na2SO4, filtered and concentrated in vacuo to afford crude ethyl 2-acetyl-5,5-dimethyl-4-oxo-hexanoate (1.46 g) which was not purified: 1H NMR (CDCl3, chemical shifts in ppm relative to TMS): 1.166 (s, 9H), 1.277 (t, 3H, J=7.1 Hz), 2.368 (s, 3H), 3.000 (dd, 1H, J=5.8 Hz, J=18.4 Hz), 3.231 (dd, 1H, J=8.2 Hz, J=18.4 Hz), 4.010 (dd, 1H, J=5.8 Hz, J=8.2 Hz), 4.191 (q, 2H, J=7.1 Hz); Field Desorption Mass Spectrometry: m/z 229 (M+1).

Workup

  1. customwas immersed in a 75° C.
  2. stirringstirred under Ar for 1 h
  3. temperatureThe reaction was cooled to rt
  4. washwashed with H2O (2×50 mL)
  5. dry with materialThe organic layer was dried over Na2SO4
  6. filtrationfiltered
  7. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-f4ba7da598ba4fada233e7114f65f501
Source dataset
uspto-grants-2004_11
Patent number
US06825356B2

Reaction notes

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