Hydrochloric Acid → 3-tert-Butyl-1-ethylcyclopenta-1,3-diene

HRID 2404927Notes

Reaction equation

HRID 2404927 reaction equation
[CH2:1]([Mg]Br)[CH3:2].[C:5]([C:9]1[CH2:13][CH2:12][C:11](=O)[CH:10]=1)([CH3:8])([CH3:7])[CH3:6].Cl>C(OCC)C>[CH2:1]([C:12]1[CH2:11][CH:10]=[C:9]([C:5]([CH3:8])([CH3:7])[CH3:6])[CH:13]=1)[CH3:2]

Participants

5

Reactant 3

HCID 313Hydrochloric AcidHCID 119769972-Cyclopenten-1-one, 3-(1,1-dimethylethyl)-HCID 178418443HCID 178418443, compound

Product 1

HCID 206271323-tert-Butyl-1-ethylcyclopenta-1,3-dieneYield 78%

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent2×

Procedure

A 300-ml three-necked flask equipped with a magnetic stirring bar and a three-way cock was charged with 200 ml of dehydrated diethyl ether and 52 ml (154 mmol) of a 3.0-M diethyl ether solution of ethyl magnesium bromide under a nitrogen atmosphere. To the solution was added dropwise 17.8 g (129 mmol) of 3-tert-butylcyclopentenone over 1 hour in an ice bath. After stirring at room temperature for 20 hours, the reaction solution was poured into 100 ml of 2N hydrochloric acid. The organic layer was separated and the aqueous layer was subjected to extraction with 50 ml of ether twice. The combined organic layer was washed with saturated sodium hydrogen carbonate aqueous solution twice, with water twice, and with saturated brine twice. After drying over magnesium sulfate, the solvent was distilled off. The residue was purified by column chromatography to obtain 20.2 g (GC purity: 75%) of pale yellow transparent liquid. The yield was 78%. The identification was carried out by 1H-NMR spectrum. The measurement results are shown below.

Workup

  1. customA 300-ml three-necked flask equipped with a magnetic stirring bar
  2. customThe organic layer was separated
  3. extractionthe aqueous layer was subjected to extraction with 50 ml of ether twice
  4. washThe combined organic layer was washed with saturated sodium hydrogen carbonate aqueous solution twice
  5. dry with materialAfter drying over magnesium sulfate
  6. distillationthe solvent was distilled off
  7. customThe residue was purified by column chromatography
  8. customto obtain 20.2 g (GC purity: 75%) of pale yellow transparent liquid
  9. customThe measurement results

Sources & evidence

ORD record
ord-928f752bbcb24124983f43405190aa45
Source dataset
uspto-grants-2014_08
Patent number
US08802779B2

Reaction notes

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