Acetic Acid → HCID 10062362, compound

HRID 257413Notes

Reaction equation

HRID 257413 reaction equation
[N:1]([O-])=O.[Na+].[CH2:5]([O:7][C:8](=[O:15])[CH:9](OC)[CH2:10][CH2:11][CH3:12])[CH3:6].[CH2:16]([O:18][C:19](=[O:24])[CH2:20]C(C)=O)[CH3:17].[C:25]([O-:28])(=O)C.[Na+].[C:30](O)(=O)[CH3:31]>[Zn]>[CH2:16]([O:18][C:19]([C:20]1[NH:1][C:30]([CH3:31])=[C:9]([C:8]([O:7][CH2:5][CH3:6])=[O:15])[C:10]=1[CH2:11][CH2:12][O:28][CH3:25])=[O:24])[CH3:17]

Participants

7

Reactant 5

HCID 176Acetic AcidHCID 8868Ethyl AcetoacetateHCID 517045Sodium AcetateHCID 23668193Sodium NitriteHCID 83038820HCID 83038820, compound

Product 1

HCID 10062362HCID 10062362, compoundYield 65%

Reagents, catalysts & solvents 1

HCID 23994ZincCatalyst

Procedure

While stirring and ice cooling, a cold saturated aqueous solution of 42 g (0.6 mol) sodium nitrite was added so slowly drop-by-drop to a solution of 104.4 g (0.6 mol) methoxypentanoic acid ethyl ester in 450 mL of glacial acetic acid, that no noticeable NOX development was detected. The solution was stirred for two hours and treated with 83.2 g (0.64 mol) acetoacetic acid ethyl ester. Then while stirring vigorously, a mixture of 80 g (1.22 mol) of zinc powder and 100 g (1.22 mol) sodium acetate was added in portions within 40 minutes. The inner temperature ranged from 80° to 85° C., a state that was reached by cooling occasionally. Following completion of the addition, the solution was stirred another 30 minutes and then filtered from the nonreacted zinc. The warm solution was poured into 4 L of water and left standing overnight to complete the precipitation. The raw product was filtered off, washed with a little ice cold ether, dried over P4O10 under vacuum for one day, and recrystallized from ethanol/water. Thus, 113.2 g (0.4 mol) 2,4-bis(ethoxycarbonyl)-3-methoxyethyl-5-methylpyrrole (2b) was obtained as colorless needles with a melting point of 86° C. Yield: 65 % based on (1b). For further reaction of (2b) it was not necessary to recrystallize the raw product from ethanol/water.

Workup

  1. stirringThe solution was stirred for two hours
  2. stirringThen while stirring vigorously
  3. additionwas added in portions within 40 minutes
  4. customranged from 80° to 85° C.
  5. temperatureby cooling occasionally
  6. additioncompletion of the addition
  7. stirringthe solution was stirred another 30 minutes
  8. filtrationfiltered from the nonreacted zinc
  9. additionThe warm solution was poured into 4 L of water
  10. waitleft
  11. customthe precipitation
  12. filtrationThe raw product was filtered off
  13. washwashed with a little ice cold ether
  14. dry with materialdried over P4O10 under vacuum for one day
  15. customrecrystallized from ethanol/water

Sources & evidence

ORD record
ord-f7b9d44f5c53484086ac022002607777
Source dataset
uspto-grants-1993_11
Patent number
US05262401

Reaction notes

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