4-Bromostyrene → (Z)-3-hexenyl 2-oxo-2-(4-vinylphenyl)acetate

HRID 630573Notes

Reaction equation

HRID 630573 reaction equation
Br[C:2]1[CH:9]=[CH:8][C:5]([CH:6]=[CH2:7])=[CH:4][CH:3]=1.[Mg].[CH2:11]([O:17][C:18](=[O:28])[C:19](OCC/C=C\CC)=[O:20])[CH2:12]/[CH:13]=[CH:14]\[CH2:15][CH3:16].[NH4+].[Cl-]>C1COCC1>[O:20]=[C:19]([C:2]1[CH:9]=[CH:8][C:5]([CH:6]=[CH2:7])=[CH:4][CH:3]=1)[C:18]([O:17][CH2:11][CH2:12]/[CH:13]=[CH:14]\[CH2:15][CH3:16])=[O:28]

Participants

6

Reactant 4

HCID 162634-BromostyreneHCID 25517Ammonium ChlorideHCID 5462224MagnesiumHCID 89488093bis[(Z)-3-hexenyl]oxalate

Product 1

HCID 89488062(Z)-3-hexenyl 2-oxo-2-(4-vinylphenyl)acetateYield 50%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

A Grignard reagent prepared from 4-bromostyrene (6.95 g, 38.0 mmol) and magnesium (0.97 g, 39.9 mmol) in THF (100 mL) was added dropwise (during a period of 20 min) to a stirred solution of bis[(Z)-3-hexenyl]oxalate (9.20 g, 36.2 mmol) in THF (35 mL) at −60° C. The mixture was left warming to room temperature and poured into a mixture of ice (100 g) and a saturated solution of NH4Cl (100 mL). Extraction with diethyl ether (200 mL, 2×), washing with a saturated solution of NaCl (50 mL, 4×, pH 7), drying (Na2SO4) and concentrating afforded 11.47 g of the crude compound as a brownish oil. Bulb-to-bulb distillation of 8.68 g of the crude product (0.06 mbar, 60° C.) and column chromatography (SiO2, heptane/ether 95:5, then 1:1, then pure ether) gave 3.53 g (50%) of an oil.

Workup

  1. waitThe mixture was left
  2. extractionExtraction with diethyl ether (200 mL, 2×)
  3. washwashing with a saturated solution of NaCl (50 mL, 4×, pH 7)
  4. dry with materialdrying (Na2SO4)
  5. concentrationconcentrating
  6. customafforded 11.47 g of the crude compound as a brownish oil
  7. distillationBulb-to-bulb distillation of 8.68 g of the crude product (0.06 mbar, 60° C.) and column chromatography (SiO2, heptane/ether 95:5

Sources & evidence

ORD record
ord-db79ccbda0ec4a02b794a6308bb651d7
Source dataset
uspto-grants-2016_04
Patent number
US09315763B2

Reaction notes

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