Ethyl cyanoacetate → 3-(4-Ethylphenyl)-2-cyano-but-2-enoic acid ethyl ester

HRID 270190

Reaction equation

HRID 270190 reaction equation
[CH2:1]([C:3]1[CH:8]=[CH:7][C:6]([C:9](=O)[CH3:10])=[CH:5][CH:4]=1)[CH3:2].[C:12]([CH2:14][C:15]([O:17][CH2:18][CH3:19])=[O:16])#[N:13].C([O-])(=O)C.[NH4+]>C(OCC)(=O)C.C(O)(=O)C.C1C=CC=CC=1>[CH2:18]([O:17][C:15](=[O:16])[C:14]([C:12]#[N:13])=[C:1]([C:3]1[CH:8]=[CH:7][C:6]([CH2:9][CH3:10])=[CH:5][CH:4]=1)[CH3:2])[CH3:19]

Participants

7

Reactant 3

HCID 7764Ethyl cyanoacetate2×HCID 136424'-EthylacetophenoneHCID 517165Ammonium Acetate2×

Product 1

HCID 44650943-(4-Ethylphenyl)-2-cyano-but-2-enoic acid ethyl ester

Reagents, catalysts & solvents 3

HCID 176Acetic AcidSolvent2×HCID 241BenzeneSolventHCID 8857Ethyl AcetateSolvent

Procedure

A mixture of 4′-ethylacetophenone (50 mmol), ethyl cyanoacetate (50 mmol), acetic acid (1.14 mL), ammonium acetate (400 mg), and benzene (50 mL) is heated to reflux in a Dean-Stark apparatus. After approximately 10 hours, additional ethyl cyanoacetate (50 mmol), acetic acid (1.14 mL), and ammonium acetate (400 mg) are added. After an additional 10 hours, the reaction is cooled to room temperature, diluted with ethyl acetate (30 mL), washed with water (240 mL), brine (40 mL), and dried (Na2SO4). After filtering, the extract is concentrated in vacuo and the desired product, as a mixture of E and Z-isomers, is isolated by column chromatography on silica gel, eluting with 5% ethyl acetate in petroleum ether.

Workup

  1. temperatureis heated
  2. temperatureto reflux in a Dean-Stark apparatus
  3. waitAfter an additional 10 hours
  4. washwashed with water (240 mL), brine (40 mL)
  5. dry with materialdried (Na2SO4)
  6. filtrationAfter filtering
  7. concentrationthe extract is concentrated in vacuo
  8. additionthe desired product, as a mixture of E and Z-isomers
  9. customis isolated by column chromatography on silica gel
  10. washeluting with 5% ethyl acetate in petroleum ether

Sources & evidence

ORD record
ord-98bcddf5215f4ed68c4e1cba9a2ae903
Source dataset
uspto-grants-2008_11
Patent number
US07449490B2

Linked notes

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