Propanethioamide → Methyl 2-ethyl-5-methyl-1,3-thiazole-4-carboxylate

HRID 2221701Notes

Reaction equation

HRID 2221701 reaction equation
Br[CH:2]([CH3:9])[C:3](=O)[C:4]([O:6][CH3:7])=[O:5].[C:10](=[S:14])([NH2:13])[CH2:11][CH3:12]>C(O)C>[CH2:11]([C:10]1[S:14][C:2]([CH3:9])=[C:3]([C:4]([O:6][CH3:7])=[O:5])[N:13]=1)[CH3:12]

Participants

4

Reactant 2

HCID 2760628PropanethioamideHCID 11183175Methyl 3-bromo-2-oxobutanoate

Product 1

HCID 23076482Methyl 2-ethyl-5-methyl-1,3-thiazole-4-carboxylateYield 53%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

A mixture of methyl 3-bromo-2-oxobutanoate (16.2 g), propanethioamide (7.4 g) and ethanol (150 mL) was heated under reflux for 3 hrs. The solvent was evaporated under reduced pressure, saturated aqueous sodium hydrogen carbonate was added to the residue and the mixture was extracted with ethyl acetate. The ethyl acetate layer was washed with saturated brine, dried over anhydrous magnesium sulfate and concentrated. The residue was subjected to silica gel column chromatography and eluted with ethyl acetate-hexane (1:4, v/v) to give methyl 2-ethyl-5-methyl-1,3-thiazole-4-carboxylate as a yellow oil (8.1 g, yield 53%).

Workup

  1. temperaturewas heated
  2. temperatureunder reflux for 3 hrs
  3. customThe solvent was evaporated under reduced pressure, saturated aqueous sodium hydrogen carbonate
  4. additionwas added to the residue
  5. extractionthe mixture was extracted with ethyl acetate
  6. washThe ethyl acetate layer was washed with saturated brine
  7. dry with materialdried over anhydrous magnesium sulfate
  8. concentrationconcentrated
  9. washeluted with ethyl acetate-hexane (1:4, v/v)

Sources & evidence

ORD record
ord-bbc1ef9f484a407aa13b9d21be20f75e
Source dataset
uspto-grants-2008_05
Patent number
US07368578B2

Reaction notes

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