Phenethyl bromide → 1,5-Diphenylpentan-3-ol

HRID 863579Notes

Reaction equation

HRID 863579 reaction equation
Br[CH2:2][CH2:3][C:4]1[CH:9]=[CH:8][CH:7]=[CH:6][CH:5]=1.[Mg].[C:11]1([CH2:17][CH2:18][CH:19]=[O:20])[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1>C(OCC)C>[C:4]1([CH2:3][CH2:2][CH:19]([OH:20])[CH2:18][CH2:17][C:11]2[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=2)[CH:9]=[CH:8][CH:7]=[CH:6][CH:5]=1

Participants

5

Reactant 3

HCID 7666Phenethyl bromideHCID 7707BenzenepropanalHCID 5462224Magnesium

Product 1

HCID 128385101,5-Diphenylpentan-3-ol

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent3×

Procedure

A solution of 2-(bromoethyl)benzene (1.73 g; 9.33 mmol) in diethylether (10 mL) was added to a stirred slurry of magnesium turnings (250 mg; 10.18 mmol) in 5 mL of ether. The reaction was initiated with a heat gun, and after the addition was complete the mixture was heated on an oil bath for 30 minutes. 3-Phenyl-1-propanal (1.25 g; 9.33 mmol) was added in 10 mL of ether, and reflux was continued for 1 hour. The reaction was cooled and quenched with saturated ammonium chloride, extracted into 2× ethyl acetate, and the combined organic portions were dried and concentrated. Chromatographic purification on a silica gel column (10% ethyl acetate in hexane) delivered 1.42 g (63%) of the diphenyl alcohol, 1H NMR (300 MHz, CDCl3): δ1.84 (m, 4H); 2.61-2.76 (m,4H); 3.65 (m, 1H); 7.19-7.29 (m, 10H).

Workup

  1. additionafter the addition
  2. temperaturewas heated on an oil bath for 30 minutes
  3. temperaturereflux
  4. temperatureThe reaction was cooled
  5. customquenched with saturated ammonium chloride
  6. extractionextracted into 2× ethyl acetate
  7. customthe combined organic portions were dried
  8. concentrationconcentrated
  9. customChromatographic purification on a silica gel column (10% ethyl acetate in hexane)

Sources & evidence

ORD record
ord-17a7ac8f85a7429aa83281c592cbb241
Source dataset
uspto-grants-1998_02
Patent number
US05721256

Reaction notes

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