p-Toluenesulfonic acid → Ethyl 2-allyl-3-(2-ethylphenyl)-3-oxopropionate

HRID 1252782Notes

Reaction equation

HRID 1252782 reaction equation
[CH2:1]([C:4]([C:17](=[O:26])[C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][C:19]=1[CH2:24][CH3:25])(C(OCC)=O)[C:5]([O:7][C:8](C)(C)[CH3:9])=[O:6])[CH:2]=[CH2:3].C(OC(=O)C)(=O)C.C1(C)C=CC(S(O)(=O)=O)=CC=1>C(O)(=O)C>[CH2:1]([CH:4]([C:17]([C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][C:19]=1[CH2:24][CH3:25])=[O:26])[C:5]([O:7][CH2:8][CH3:9])=[O:6])[CH:2]=[CH2:3]

Participants

5

Reactant 3

HCID 6101p-Toluenesulfonic acidHCID 7918Acetic AnhydrideHCID 19809551t-Butyl ethyl 2-allyl-2-(2-ethylbenzoyl)malonate

Product 1

HCID 13459157Ethyl 2-allyl-3-(2-ethylphenyl)-3-oxopropionateYield 71.6%

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Conditions

Temperature
140 °C

Procedure

A mixture of t-butyl ethyl 2-allyl-2-(2-ethylbenzoyl)malonate (14.3 g.), acetic anhydride (4 ml.) and p-toluenesulphonic acid (100 mg.) in acetic acid (200 ml.) was heated at 140° C. under nitrogen for 75 minutes and then evaporated. The residue was shaken with a mixture of saturated sodium bicarbonate solution (100 ml.) and ethyl acetate (100 ml.). The organic phase was dried (MgSO4) and evaporated. The oil obtained (9.3 g.) was purified by flash column chromatography (280 g.) using toluene as eluant to give ethyl 2-allyl-3-(2-ethylphenyl)-3-oxopropionate (7.4 g.) as a pale yellow oil; NMR: 1.19 (6H,m), 2.74 (4H,m), 4.15 (3H,m), 5.05 (2H,m), 5.79 (1H,m), 7.30 (3H,m) and 7.61 (1H,m) ppm.

Workup

  1. customevaporated
  2. dry with materialThe organic phase was dried (MgSO4)
  3. customevaporated
  4. customThe oil obtained (9.3 g.)
  5. customwas purified by flash column chromatography (280 g.)

Sources & evidence

ORD record
ord-4a212d9d183144e7b1fcd4c850a9fd03
Source dataset
uspto-grants-1988_05
Patent number
US04745198

Reaction notes

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