Diethyl (ethoxymethylene)malonate → HCID 178469978, compound

HRID 443491

Reaction equation

HRID 443491 reaction equation
[N+:1]([C:4]1[CH:9]=[CH:8][CH:7]=[CH:6][C:5]=1[NH:10][NH2:11])([O-:3])=[O:2].C([O:14][CH:15]=[C:16]([C:22](OCC)=O)[C:17]([O:19][CH2:20][CH3:21])=[O:18])C>C(O)C>[OH:14][C:15]1[N:10]([C:5]2[CH:6]=[CH:7][CH:8]=[CH:9][C:4]=2[N+:1]([O-:3])=[O:2])[N:11]=[CH:22][C:16]=1[C:17]([O:19][CH2:20][CH3:21])=[O:18]

Participants

4

Reactant 2

HCID 6871Diethyl (ethoxymethylene)malonateHCID 3314739(2-Nitrophenyl)hydrazine

Product 1

HCID 178469978HCID 178469978, compoundYield 43.9%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

102 g (2-nitrophenyl)hydrazine and 142 g (Ethoxymethylene)propanedioic acid, diethyl ester are dissolved in 300 ml ethanol and refluxed for 20 hours. After cooling the clear red solution is evaporated and the solvent distilled off. The remaining crystalline residue (168 g) is added to 400 g PPA (polyphosphoric acid) at a temperature of 80° C. The reaction is completed by heating the solution for 10 minutes to 120° C. The solution is then immediately poured on 2 kg ice and stirred for 30 minutes. After filtration the residue is recrystallized from n-propanol to yield 80 g of 5-hydroxy-1-(2-nitrophenyl)-1H-pyrazole-4-carboxylic acid, ethyl ester with a melting point of 157°-160° C.; yellow crystals.

Workup

  1. temperaturerefluxed for 20 hours
  2. temperatureAfter cooling the clear red solution
  3. customis evaporated
  4. distillationthe solvent distilled off
  5. additionThe remaining crystalline residue (168 g) is added to 400 g PPA (polyphosphoric acid) at a temperature of 80° C
  6. temperatureby heating the solution for 10 minutes to 120° C
  7. additionThe solution is then immediately poured on 2 kg ice
  8. filtrationAfter filtration the residue
  9. customis recrystallized from n-propanol

Sources & evidence

ORD record
ord-5bc60e2de038415b9acb005ffd3ccbf1
Source dataset
uspto-grants-1981_04
Patent number
US04260751

Linked notes

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