o-Vanillin → Phenol, 2-ethenyl-6-methoxy-

HRID 902288Notes

Reaction equation

HRID 902288 reaction equation
[CH2:1]([Li])CCC.O=[CH:7][C:8]1[CH:16]=[CH:15][CH:14]=[C:11]([O:12][CH3:13])[C:9]=1[OH:10]>[Br-].C[P+](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1.O1CCCC1>[CH3:13][O:12][C:11]1[CH:14]=[CH:15][CH:16]=[C:8]([CH:7]=[CH2:1])[C:9]=1[OH:10]

Participants

5

Reactant 2

HCID 8991o-VanillinHCID 178418339Butyllithium

Product 1

HCID 183539Phenol, 2-ethenyl-6-methoxy-

Reagents, catalysts & solvents 2

HCID 74505Methyltriphenyliphosphonium bromideCatalystHCID 8028TetrahydrofuranSolvent2×

Conditions

Temperature
0 °C

Procedure

A suspension of methyltriphenylphosphonium bromide (19.7 g, 55.0 mmol) in anhydrous tetrahydrofuran (200 mL) was cooled to 0° C. and n-butyllithium (2.5 M in hexanes, 24.0 mL, 60.0 mmol) was added during 5–10 minutes with stirring. The resulting clear, orange solution was stirred at 0° C. for an additional 30 minutes and then was added via cannula to a solution of o-vanillin (3.80 g, 25.0 mmol) in tetrahydrofuran (100 mL) at 23° C. After 3 hours, the reaction was quenched with saturated aqueous ammonium chloride solution (100 mL), diluted with water (300 mL), and the aqueous phase was extracted with ether (3×200 mL). The organic phase was washed with water (300 mL) and brine (300 mL), dried over magnesium sulfate and filtered through a plug of silica gel (10 cm diam×5–6 cm H). Concentration under reduced pressure provided crude 2-methoxy-6-vinyl-phenol as a clear, colorless oil (4.20 g) that was used without further purification. 1H NMR (DMSO): δ3.79 (s, 3 H, OCH3), 5.19 (dd, 1H, CH═CHH), 5.74 (dd, 1H, CH═CHH), 6.74 (t, 1H, ArH), δ6.86 (dd, 1H, ArH), 6.96 (dd, 1H, CH═CHH), 7.04 (dd, 1H, ArH), and 8.74 (s, 1H, ArOH).

Workup

  1. stirringThe resulting clear, orange solution was stirred at 0° C. for an additional 30 minutes
  2. customthe reaction was quenched with saturated aqueous ammonium chloride solution (100 mL)
  3. additiondiluted with water (300 mL)
  4. extractionthe aqueous phase was extracted with ether (3×200 mL)
  5. washThe organic phase was washed with water (300 mL) and brine (300 mL)
  6. dry with materialdried over magnesium sulfate
  7. filtrationfiltered through a plug of silica gel (10 cm diam×5–6 cm H)
  8. concentrationConcentration under reduced pressure

Sources & evidence

ORD record
ord-3cefb62865af406f8552a2ead322039c
Source dataset
uspto-grants-2008_04
Patent number
US07365095B2

Reaction notes

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