2-Naphthalenecarboxaldehyde → 1-(2-Naphthyl)-6-heptenol

HRID 1182501Notes

Reaction equation

HRID 1182501 reaction equation
[Mg].BrCCBr.Br[CH2:7][CH2:8][CH2:9][CH2:10][CH:11]=[CH2:12].[CH:13]1[C:22]2[C:17](=[CH:18][CH:19]=[CH:20][CH:21]=2)[CH:16]=[CH:15][C:14]=1[CH:23]=[O:24]>C1COCC1>[CH:13]1[C:22]2[C:17](=[CH:18][CH:19]=[CH:20][CH:21]=2)[CH:16]=[CH:15][C:14]=1[CH:23]([OH:24])[CH2:12][CH2:11][CH2:10][CH2:9][CH:8]=[CH2:7]

Participants

6

Reactant 4

HCID 62012-NaphthalenecarboxaldehydeHCID 78391,2-DibromoethaneHCID 759066-Bromo-1-hexeneHCID 5462224Magnesium2×

Product 1

HCID 230723861-(2-Naphthyl)-6-heptenolYield 89%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent3×

Procedure

A flame-dried round-bottomed flask was charged with magnesium turnings (1.23 g, 50.75 mmol) and stirred under vacuum for 15 minutes and then applied under nitrogen atmosphere. THF (70 mL) was added followed by 1,2-dibromoethane (381 mg, 2.03 mmol), and the mixture was brought to the boiling point for 1 minute, then and cooled down to room temperature. A solution of 6-bromohexene (8.28 g, 50.75 mmol) in THF (30 mL) was transferred via cannula to the magnesium flask and the mixture was refluxed overnight and cooled to −78° C. A solution of 2-naphthaldehyde (6.10 g, 39.04 mmol) in THF (30 mL) was transferred via cannula to the Grignard reagent and the mixture was slowly warmed to 0° C. over 3 hours and kept at that temperature for 2 hours. The reaction was quenched with a saturated aqueous ammonium chloride solution and THF was evaporated in vacuo. The aqueous residue was poured into a separating funnel containing water and the compound was extracted with diethyl ether (2×100 mL). The combined organic layers were washed with brine, dried over magnesium sulfate and concentrated. The residue was purified by flash chromatography (10% to 15% ethyl acetate in hexane), affording the title compound 181 in 89% yield (8.33g). 1H NMR: (300 MHz, CDCl3) δ: 7.85-7.78 (m, 4H), 7.51-7.44 (m, 3H), 5.85-5.72 (m, 1H), 5.02-4.91 (m, 2H), 4.87-4.82 (m, 2H), 2.08-2.01 (m, 2H), 1.94-1.80 (m, 2H), 1.53-1.23(m, 4H). MS (ESI)=223 (MH+—H2O).

Workup

  1. waitthe mixture was brought to the boiling point for 1 minute
  2. temperaturethe mixture was refluxed overnight
  3. temperaturecooled to −78° C
  4. temperaturethe mixture was slowly warmed to 0° C. over 3 hours
  5. waitkept at that temperature for 2 hours
  6. customThe reaction was quenched with a saturated aqueous ammonium chloride solution and THF
  7. customwas evaporated in vacuo
  8. additionThe aqueous residue was poured into a separating funnel
  9. additioncontaining water
  10. extractionthe compound was extracted with diethyl ether (2×100 mL)
  11. washThe combined organic layers were washed with brine
  12. dry with materialdried over magnesium sulfate
  13. concentrationconcentrated
  14. customThe residue was purified by flash chromatography (10% to 15% ethyl acetate in hexane)

Sources & evidence

ORD record
ord-ce2f46e154de489c993993ed3d2cb187
Source dataset
uspto-grants-2007_10
Patent number
US07288567B2

Reaction notes

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