tert-Butanol → 1-benzyl 5-tert-butyl (5S)-2-oxoimidazolidine-1,5-dicarboxylate

HRID 1980293Notes

Reaction equation

HRID 1980293 reaction equation
[CH2:1]([O:8][C:9]([N:11]1[C@H:15]([C:16]([OH:18])=[O:17])[CH2:14][NH:13][C:12]1=[O:19])=[O:10])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[C:20](O)([CH3:23])([CH3:22])[CH3:21].P(Cl)(Cl)(Cl)=O>N1C=CC=CC=1>[CH2:1]([O:8][C:9]([N:11]1[C@H:15]([C:16]([O:18][C:20]([CH3:23])([CH3:22])[CH3:21])=[O:17])[CH2:14][NH:13][C:12]1=[O:19])=[O:10])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1

Participants

5

Reactant 3

HCID 6386tert-ButanolHCID 24813Phosphorus oxychlorideHCID 688196(S)-(-)-2-Oxo-1,5-imidazolidinedicarboxylic acid 1-benzyl ester

Product 1

HCID 110671601-benzyl 5-tert-butyl (5S)-2-oxoimidazolidine-1,5-dicarboxylateYield 89%

Reagents, catalysts & solvents 1

HCID 1049PyridineSolvent

Procedure

5.1 g of (4S)-3-benzyloxycarbonyl-2-oxo-imidazolidine-4-carboxylic acid (Liebich's Annalen der Chemie 529 (1937), page 1) are dissolved in 20 ml of pyridine, and 50 ml of tert.-butanol are added thereto. The solution is cooled to a temperature below -5° C., and 3.5 g of phosphorous oxychloride are added dropwise thereto. The mixture is stirred at the same temperature for about 30 minutes and then at room temperature for 3 hours. The reaction mixture is poured into 200 ml of ice-water, and extracted with ethyl acetate. The extract is washed with 1% hydrochloric acid, an aqueous sodium bicarbonate solution and water, successively. Then, the extract is dried and evaporated to remove solvent. The residue obtained is crystallized with a mixture of ether and n-hexane. 5.5 g of tert.-butyl (4S)-3-benzyloxycarbonyl-2-oxo-imidazolidine-4-carboxylate are obtained as colorless crystals. Yield: 89.0%

Workup

  1. additionare added dropwise
  2. waitat room temperature for 3 hours
  3. extractionextracted with ethyl acetate
  4. washThe extract is washed with 1% hydrochloric acid
  5. customThen, the extract is dried
  6. customevaporated
  7. customto remove solvent
  8. customThe residue obtained
  9. customis crystallized with a mixture of ether and n-hexane

Sources & evidence

ORD record
ord-7ab2beeafb4b4018b5a1036bb6132983
Source dataset
uspto-grants-1985_04
Patent number
US04508727

Reaction notes

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