Ethyl Acetoacetate → Ethyl 2-acetyl-3-(dimethylamino)acrylate

HRID 1419690Notes

Reaction equation

HRID 1419690 reaction equation
[C:1]([CH2:4][C:5]([O:7][CH2:8][CH3:9])=[O:6])(=[O:3])[CH3:2].CO[CH:12](OC)[N:13]([CH3:15])[CH3:14]>C1C=CC=CC=1>[CH3:12][N:13]([CH:15]=[C:4]([C:1](=[O:3])[CH3:2])[C:5]([O:7][CH2:8][CH3:9])=[O:6])[CH3:14]

Participants

4

Reactant 2

HCID 8868Ethyl AcetoacetateHCID 78373Dimethylformamide dimethyl acetal

Product 1

HCID 3806790Ethyl 2-acetyl-3-(dimethylamino)acrylateYield 101.6%

Reagents, catalysts & solvents 1

HCID 241BenzeneSolvent2×

Procedure

To a solution of ethyl acetylacetate (6 g, 46 mmol) in benzene (100 mL) was slowly added a solution of dimethylformamide dimethylacetal (8.2 g, 69 mmol) in benzene (100 mL) at 25° C. After the addition was complete, the reddish mixture was heated at reflux for 1 h and then evaporated to dryness to give ethyl 2-dimethylaminomethylene-3-oxobutanoate (8.66 g) as a reddish oil. This product (3.25 g, 17 mmol) was allowed to react with 4-chlorophenylhydrazine hydrochloride (3.14 g, 17 mmol) in EtOH (50 mL) at reflux for 8 h. The mixture was evaporated to dryness and the product was isolated by flash chromatography to give ethyl 1-(4-chlorophenyl)-5-methyl-1H-pyrazole-4-carboxylate as a white solid (2.07 g, 46%): mp 55°-56° C.; 1H NMR (80 MHz, CDCl3) δ (TMS) 8.02 (s, 1H, pyrazole), 7.50 (d, J=9, 2H, arom), 7.34 (d, J=9, 2H, arom), 4.33 (q, J=7, 2H, OCH2), 2.56 (s, 3H, Me-pyrazole), 1.37 (t, J=7, 3H, OCH2CH3). Analysis calculated for C13H13ClN2O2 : C 58.99; H 4.95; N 10.58. Found: C 59.03; H 5.06; N 10.58.

Workup

  1. additionAfter the addition
  2. temperaturethe reddish mixture was heated
  3. temperatureat reflux for 1 h
  4. customevaporated to dryness

Sources & evidence

ORD record
ord-b7be858c839844efac1189bfba6d2914
Source dataset
uspto-grants-1999_03
Patent number
US05888941

Reaction notes

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