Hydroquinone → (E)-3,7-dimethylocta-2,6-dien-1-yl 2-oxo-2-(4-vinylphenyl)acetate

HRID 630571Notes

Reaction equation

HRID 630571 reaction equation
Br[C:2]1[CH:9]=[CH:8][C:5]([CH:6]=[CH2:7])=[CH:4][CH:3]=1.[Mg].[CH3:11]/[C:12](/[CH2:31][CH2:32][CH:33]=[C:34]([CH3:36])[CH3:35])=[CH:13]\[CH2:14][O:15][C:16](=[O:30])[C:17](OC/C=C(\C)/CCC=C(C)C)=[O:18].[NH4+].[Cl-].C1(C=CC(O)=CC=1)O>C1COCC1.CCCCCCC.CCOCC>[O:18]=[C:17]([C:2]1[CH:9]=[CH:8][C:5]([CH:6]=[CH2:7])=[CH:4][CH:3]=1)[C:16]([O:15][CH2:14]/[CH:13]=[C:12](\[CH3:11])/[CH2:31][CH2:32][CH:33]=[C:34]([CH3:36])[CH3:35])=[O:30]

Participants

8

Reactant 5

HCID 785HydroquinoneHCID 162634-BromostyreneHCID 25517Ammonium ChlorideHCID 5462224MagnesiumHCID 88341515Geranyl oxalate

Product 1

HCID 89487941(E)-3,7-dimethylocta-2,6-dien-1-yl 2-oxo-2-(4-vinylphenyl)acetateYield 21%

Reagents, catalysts & solvents 2

HCID 8028TetrahydrofuranSolvent2×HCID 21897273Diethylether heptaneSolvent

Procedure

A Grignard reagent prepared from 4-bromostyrene (2.78 g, 15.2 mmol) and magnesium (0.39 g, 15.9 mmol) in THF (23 mL) was added dropwise (during 20 min) to a stirred solution of (E)-bis(3,7-dimethylocta-2,6-dien-1-yl)oxalate (5.00 g, 13.8 mmol) in THF (40 mL) at −60° C. The mixture was left warming to room temperature, and then poured into a mixture of ice (70 g) and a saturated solution of NH4Cl (60 mL). Extraction with diethyl ether (200 mL), washing with a saturated solution of NaCl (100 mL, 3×), drying (Na2SO4), adding of hydroquinone (10 mg) and concentrating afforded 6.44 g of the crude compound. Repetitive column chromatography (SiO2, heptane/ether 9:1 and 98:2), addition of hydroquinone to the product fraction, concentration and drying under vacuum (0.2 mbar, 1 h) gave 0.90 g (21%) of an oil.

Workup

  1. waitThe mixture was left
  2. extractionExtraction with diethyl ether (200 mL)
  3. washwashing with a saturated solution of NaCl (100 mL, 3×)
  4. dry with materialdrying (Na2SO4)
  5. additionadding of hydroquinone (10 mg)
  6. concentrationconcentrating
  7. customafforded 6.44 g of the crude compound
  8. concentrationto the product fraction, concentration
  9. customdrying under vacuum (0.2 mbar, 1 h)

Sources & evidence

ORD record
ord-a83c6a3ba2414e86bde0fbdede9fb496
Source dataset
uspto-grants-2016_04
Patent number
US09315763B2

Reaction notes

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