Ethanol → Diethyl 1-benzyl-3,4-dihydroxy-1H-pyrrole-2,5-dicarboxylate

HRID 2308158Notes

Reaction equation

HRID 2308158 reaction equation
C(O)C.[Na].[CH2:5]([N:12]([CH2:19][C:20]([O:22][CH2:23][CH3:24])=[O:21])[CH2:13][C:14]([O:16][CH2:17][CH3:18])=[O:15])[C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1.[C:25](OCC)(=[O:31])[C:26](OCC)=[O:27]>C(O)(=O)C>[CH2:5]([N:12]1[C:13]([C:14]([O:16][CH2:17][CH3:18])=[O:15])=[C:26]([OH:27])[C:25]([OH:31])=[C:19]1[C:20]([O:22][CH2:23][CH3:24])=[O:21])[C:6]1[CH:7]=[CH:8][CH:9]=[CH:10][CH:11]=1

Participants

6

Reactant 4

HCID 702EthanolHCID 7268Diethyl OxalateHCID 5235503Diethyl benzyliminodiacetateHCID 5360545Sodium2×

Product 1

HCID 54682554Diethyl 1-benzyl-3,4-dihydroxy-1H-pyrrole-2,5-dicarboxylateYield 57.9%

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Procedure

Into a 20L three-necked flask, 2.7L of ethanol was put, and 139.2 g (6.05 moles) of small cuts of metallic sodium were gradually added thereto with stirring at room temperature. After the addition was completed, the mixture was stirred under reflux until the metallic sodium became dissolved completely. The mixture formed was cooled to room temperature, and 770.7 g (2.760 moles) of the diethyl N-benzyliminodiacetate and 405.8 g (2.775 moles) of diethyl oxalate were added thereto, which were then stirred under reflux for 8 hours. After the reaction was completed, the reaction product was left to cool, and its pH was adjusted to 5.5 by adding 4.5L of acetic acid. The precipitate formed was collected by filtration and washed with water. This precipitate was washed with acetone to obtain 532.8 g of diethyl N-benzyl-3,4-dihydroxypyrrole-2,5-dicarboxylate (yield: 57.9%), having a melting point of 143.5 to 145.0° C.

Workup

  1. additionAfter the addition
  2. stirringthe mixture was stirred
  3. dissolutionbecame dissolved completely
  4. customThe mixture formed
  5. temperaturewas cooled to room temperature
  6. stirringwhich were then stirred
  7. temperatureunder reflux for 8 hours
  8. waitthe reaction product was left
  9. temperatureto cool
  10. customThe precipitate formed
  11. filtrationwas collected by filtration
  12. washwashed with water
  13. washThis precipitate was washed with acetone

Sources & evidence

ORD record
ord-1617fad6d8f642d9a03291f62247bb4d
Source dataset
uspto-grants-2004_12
Patent number
US06835471B2

Reaction notes

Loading…