2-Aminothiazole → 2-Thiazolecarbamic acid, ethyl ester

HRID 851788Notes

Reaction equation

HRID 851788 reaction equation
[NH2:1][C:2]1[S:3][CH:4]=[CH:5][N:6]=1.Cl[C:8]([O:10][CH2:11][CH3:12])=[O:9].C(OCC)(=O)C>N1C=CC=CC=1>[C:8]([NH:1][C:2]1[S:3][CH:4]=[CH:5][N:6]=1)([O:10][CH2:11][CH3:12])=[O:9]

Participants

5

Reactant 3

HCID 21552-AminothiazoleHCID 8857Ethyl AcetateHCID 10928Ethyl chloroformate

Product 1

HCID 772412-Thiazolecarbamic acid, ethyl esterYield 43.4%

Reagents, catalysts & solvents 1

HCID 1049PyridineSolvent

Procedure

To a stirred solution of 15.1 g (151 mmole) of 2-aminothiazole in 200 ml of dry pyridine is added slowly 18.8 g (173 mmole) of ethyl chloroformate. After approximately 1 day, insolubles are removed by filtration and discarded and the filtrate is concentrated at reduced pressure. The resultant gum is dissolved in aqueous ethanol and redried in vacuo to a sticky solid. The crude product is dissolved in a boiling mixture of 100 ml of ethanol and 25 ml of water, clarified by filtration, and allowed to cool. The resultant crystalline solid is collected and washed thoroughly with water, giving 11.3 g (65.6 mmole) of 2-carbethoxyaminothiazole as a tlc-homogeneous (ethyl acetate eluent on silica gel plates) substance. Structure assignment is supported by the nmr spectrum.

Workup

  1. custominsolubles are removed by filtration
  2. concentrationthe filtrate is concentrated at reduced pressure
  3. dissolutionThe resultant gum is dissolved in aqueous ethanol
  4. customredried in vacuo to a sticky solid
  5. dissolutionThe crude product is dissolved in a boiling mixture of 100 ml of ethanol and 25 ml of water
  6. filtrationclarified by filtration
  7. temperatureto cool
  8. customThe resultant crystalline solid is collected
  9. washwashed thoroughly with water

Sources & evidence

ORD record
ord-d6e1cc3a826e476e880150838669176a
Source dataset
uspto-grants-1983_05
Patent number
US04386211

Reaction notes

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