Urea → Dimethylhydantoin

HRID 904720Notes

Reaction equation

HRID 904720 reaction equation
[Na].O[C:3]([CH3:10])([CH3:9])[C:4]([O:6]CC)=O.[NH2:11][C:12]([NH2:14])=[O:13]>C(O)C>[CH3:9][C:3]1([CH3:10])[NH:14][C:12](=[O:13])[NH:11][C:4]1=[O:6]

Participants

5

Reactant 3

HCID 1176UreaHCID 6653Ethyl 2-hydroxyisobutyrateHCID 5360545Sodium

Product 1

HCID 6491DimethylhydantoinYield 52.7%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Conditions

Temperature
100 °C

Procedure

In a 5-liter three neck distillation flask were placed 1.5 l of ethanol, 92 g of metallic sodium, 472 g of ethyl α-hydroxyisobutyrate (4 mole), and 240 g of urea (4 mole). The mixture was heated and stirred on hot oil bath at 100° C. for 18 hours. After ethanol and methanol were distilled off from the reaction mixture and then 2 l of water was added therefor, the mixture was made acid with aqueous hydrochloric acid solution and then extracted twice with ethyl acetate. The extract was dried with Glauber's salt, and then filtered. The solvent was distilled off from the extract to obtain 270 g of 5,5-dimethylhydantoin having a melting point of 75° C.

Workup

  1. distillationIn a 5-liter three neck distillation flask
  2. temperatureThe mixture was heated
  3. distillationAfter ethanol and methanol were distilled off from the reaction mixture
  4. addition2 l of water was added
  5. extractionextracted twice with ethyl acetate
  6. dry with materialThe extract was dried with Glauber's salt
  7. filtrationfiltered
  8. distillationThe solvent was distilled off from the
  9. extractionextract

Sources & evidence

ORD record
ord-3f927c0a3bf04fb4b4bde1265d5024d0
Source dataset
uspto-grants-1983_12
Patent number
US04419443

Reaction notes

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