Methyl acetoacetate → Cyclopropanecarboxylic acid, 1-acetyl-2-ethenyl-, methyl ester

HRID 1154057Notes

Reaction equation

HRID 1154057 reaction equation
[CH2:1](Cl)/[CH:2]=[CH:3]/[CH2:4]Cl.[C:7]([O:13][CH3:14])(=[O:12])[CH2:8][C:9]([CH3:11])=[O:10].[Na]CC(=O)CC(OC)=O.[Na]>CO>[C:9]([C:8]1([C:7]([O:13][CH3:14])=[O:12])[CH2:4][CH:3]1[CH:2]=[CH2:1])(=[O:10])[CH3:11]

Participants

6

Reactant 4

HCID 7757Methyl acetoacetateHCID 6421971,4-Dichloro-2-butene, (2E)-2×HCID 5360545SodiumHCID 178500920HCID 178500920, compound

Product 1

HCID 10964908Cyclopropanecarboxylic acid, 1-acetyl-2-ethenyl-, methyl ester

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent2×

Procedure

Methyl 1-acetyl-2-vinylcyclopropane-1-carboxylate was prepared by the reaction of 1,4-dichlorobutene-2 and methyl acetoacetate using the classical condensation procedure. For the reaction, methyl sodioacetoacetate was prepared by first reacting 36.6 grams sodium metal with 500 mls anhydrous methanol and then adding 185.6 grams of the methyl acetoacetic ester. The resulting solution was then added dropwise, at a rate sufficient to maintain reflux, to 100 grams 1,4-dichlorobutene-2 in 200 mls methanol under a nitrogen atmosphere. After addition was complete, refluxing was continued for 3 hours followed by stirring overnight at ambient temperature. The resulting reaction product (IA) was then stripped under reduced pressure after filtering to remove insoluble salts. Fractional distillation yielded 55 percent yield of a product (IB) consisting predominantly of the desired vinylcyclopropane product (boiling point 83.5° C.-85.0° C. at 4.5 mm Hg; nD22° 1.4705). Nuclear magnetic resonance spectroscopy and gas chromatographic analysis of IB showed the product to consist of 85.7 percent methyl 1-acetyl-2-vinylcyclopropane-1-carboxylate and 14.3 percent 4-carbomethoxy-5-methyl-2-vinyl-2,3-dihydrofuran.

Workup

  1. customthe classical condensation procedure
  2. customwas prepared
  3. additionThe resulting solution was then added dropwise, at a rate sufficient
  4. temperatureto maintain
  5. additionAfter addition
  6. temperaturerefluxing
  7. customThe resulting reaction product (IA)
  8. filtrationafter filtering
  9. customto remove insoluble salts
  10. distillationFractional distillation

Sources & evidence

ORD record
ord-41248321da734e538d186bf9086a4a69
Source dataset
uspto-grants-1984_12
Patent number
US04487946

Reaction notes

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