Allyl bromide → 2-Phenyl-2-methyl-4-pentenoyl cyclohexane

HRID 991444Notes

Reaction equation

HRID 991444 reaction equation
CC([O-:5])(C)C.[K+].[C:7]1([CH:13]([C:15]([CH:17]2[CH2:22][CH2:21][CH2:20][CH2:19][CH2:18]2)=O)[CH3:14])[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1.[CH2:23](Br)[CH:24]=[CH2:25]>C1COCC1>[C:7]1([C:13]2([CH3:14])[CH2:15][CH:17]([C:22](=[O:5])[CH:21]=[CH:20][CH2:19][CH3:18])[CH2:25][CH2:24][CH2:23]2)[CH:8]=[CH:9][CH:10]=[CH:11][CH:12]=1

Participants

5

Reactant 3

HCID 7841Allyl bromideHCID 142241151-Cyclohexyl-2-phenylpropan-1-oneHCID 23665647Potassium tert-butoxide

Product 1

HCID 694234192-Phenyl-2-methyl-4-pentenoyl cyclohexaneYield 91.6%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent3×

Procedure

A solution of 31.39 g (0.2797 mol) of t-BuOK in 100 mL of THF was added dropwise to a solution of 55.00 g (0.2543 mol) of cyclohexyl 1-phenylethyl ketone and 26.4 mL (0.3052 mol) of allyl bromide in 136 mL of THF (cooled in a wet ice acetone bath). THF washings (16 mL) were added to the reaction mixture. The cooling bath was removed after addition. After reaction completion (2 h), the reaction mixture was quenched with 300 mL of 1 N HCl (pH=0) and extracted with 300 mL of heptane. The heptane extract was washed with 10% NaHCO3 (aq) (pH=9), dried over MgSO4, gravity filtered and concentrated under vacuum to afford 59.70 g (91.58%) of title compound as an amber oil: 1H NMR (d6-DMSO): δ 7.32-7.42 (m, 2H, phenyl CH), 7.24-7.31 (m, 3H, phenyl CH), 5.34-5.47 (m, 1H, —CH═CH2), 5.02 (dd, J=17.1 Hz, J=2.1 Hz, 1H, —CH═CH—H (trans)), 4.97 (ddd, J=10.2 Hz, J=2.2 Hz, J=1.0 Hz, 1H, —CH═CH—H (cis, W-coupling)), 2.66 (ddd, J=14.2 Hz, J=6.9 Hz, J=1.0 Hz, 1H, —CH2CH═CH2), 2.59 (ddd, J=14.2 Hz, J=7.3 Hz, J=1.0 Hz, 1H, —CH2CH═CH2), 2.38-2.49 (m, 1H, cyclohexyl CH), 1.48-1.69 (m, 4H, cyclohexyl —CH2), 1.46 (s, 3H, —CH(CH3)Ph), 1.36-1.44 (m, 1H, cyclohexyl —CH2), 0.82-1.36 (m, 5H, cyclohexyl —CH2).

Workup

  1. customThe cooling bath was removed
  2. additionafter addition
  3. customAfter reaction completion (2 h)
  4. customthe reaction mixture was quenched with 300 mL of 1 N HCl (pH=0)
  5. extractionextracted with 300 mL of heptane
  6. extractionThe heptane extract
  7. washwas washed with 10% NaHCO3 (aq) (pH=9)
  8. dry with materialdried over MgSO4, gravity
  9. filtrationfiltered
  10. concentrationconcentrated under vacuum

Sources & evidence

ORD record
ord-40061c2321d04e77ae537b1b137866cb
Source dataset
uspto-grants-2002_10
Patent number
US06465453B1

Reaction notes

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