Hydrochloric Acid → 5-Benzyl-3,6-dioxo-2-piperazine acetic acid methyl ester

HRID 868714Notes

Reaction equation

HRID 868714 reaction equation
Cl.C([NH:4][C@H:5]([C:10]([NH:12][C@H:13]([C:21]([OH:23])=O)[CH2:14][C:15]1[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=1)=[O:11])[CH2:6][C:7](=[O:9])[OH:8])=O.[CH2:24](N(CC)CC)C>CO>[CH3:24][O:8][C:7](=[O:9])[CH2:6][CH:5]1[C:10](=[O:11])[NH:12][CH:13]([CH2:14][C:15]2[CH:16]=[CH:17][CH:18]=[CH:19][CH:20]=2)[C:21](=[O:23])[NH:4]1

Participants

5

Reactant 3

HCID 313Hydrochloric AcidHCID 8471TriethylamineHCID 92472N-(N-Formyl-L-alpha-aspartyl)-3-phenyl-L-alanine

Product 1

HCID 138837735-Benzyl-3,6-dioxo-2-piperazine acetic acid methyl esterYield 72.8%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

To a solution having 9.6 g of hydrogen chloride dissolved in 400 ml of methanol was fed 61.6 g of N-formyl-α-L-aspartyl-L-phenylalanine and the resulting mixture was reacted at 50°-60° C. for 6 hours. The resulting reaction solution was cooled to room temperature, added dropwise with 30.4 g of triethylamine, and then subjected to further reaction under reflux for 8 hours. The reaction mixture was cooled to room temperature and the crystal thereby deposited was filtered and washed with methanol to obtain 40.2 g of 5-benzyl-3,6-dioxo-2-piperazine acetic acid methyl ester having a melting point of 216°-218° C.

Workup

  1. customthe resulting mixture was reacted at 50°-60° C. for 6 hours
  2. customThe resulting reaction solution
  3. customsubjected to further reaction
  4. temperatureunder reflux for 8 hours
  5. temperatureThe reaction mixture was cooled to room temperature
  6. filtrationthe crystal thereby deposited was filtered
  7. washwashed with methanol

Sources & evidence

ORD record
ord-52135ddbea8a442491efeb1586bf2a83
Source dataset
uspto-grants-1988_10
Patent number
US04780561

Reaction notes

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