Diethyl 2-(ethoxymethylidene)-3-oxobutanedioate → HCID 19958265, compound

HRID 1898839Notes

Reaction equation

HRID 1898839 reaction equation
[NH2:1][C:2]1[O:6][N:5]=[C:4]([CH3:7])[CH:3]=1.C(O[CH:11]=[C:12]([C:18]([C:20]([O:22][CH2:23][CH3:24])=[O:21])=O)[C:13]([O:15][CH2:16][CH3:17])=[O:14])C>C(O)(=O)C>[CH3:7][C:4]1[C:3]2[C:2](=[N:1][C:18]([C:20]([O:22][CH2:23][CH3:24])=[O:21])=[C:12]([C:13]([O:15][CH2:16][CH3:17])=[O:14])[CH:11]=2)[O:6][N:5]=1

Participants

4

Reactant 2

HCID 40590Diethyl 2-(ethoxymethylidene)-3-oxobutanedioateHCID 845905-Amino-3-methylisoxazole

Product 1

HCID 19958265HCID 19958265, compoundYield 40.8%

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Procedure

5-Amino-3-methylisoxazole (12.25 g, 0.125 mol) and diethyl (ethoxymethylene)oxalacetate (33.55 g, 0.138 mol) are dissolved in 200 mL glacial acetic acid under an N2 atmosphere. The solution is heated to reflux for hours, then stirred at room temperature for 65 hours. The solution is poured into ice water, causing the precipitation of a red solid. The solid is collected by filtration, redissolved in 175 mL glacial acetic acid and reprecipitated with the addition of ice. The resulting yellow sol is collected by filtration and air dried, giving 14.20 g of product, yield 40.8%, having melting point 95°-99° C. A small amount is recrystallized from hexanes/ethyl acetate, melting point 100°-101° C.

Workup

  1. temperatureThe solution is heated
  2. temperatureto reflux for hours
  3. customthe precipitation of a red solid
  4. filtrationThe solid is collected by filtration
  5. dissolutionredissolved in 175 mL glacial acetic acid
  6. customreprecipitated with the addition of ice
  7. filtrationThe resulting yellow sol is collected by filtration and air
  8. customdried

Sources & evidence

ORD record
ord-df6fec89b3f742dd83e1820b80b694b0
Source dataset
uspto-grants-1996_11
Patent number
US05571773

Reaction notes

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