Ethyl bromopyruvate → Ethyl 2-ethyl-1,3-thiazole-4-carboxylate

HRID 446409Notes

Reaction equation

HRID 446409 reaction equation
Br[CH2:2][C:3](=O)[C:4]([O:6][CH2:7][CH3:8])=[O:5].[C:10](=[S:14])([NH2:13])[CH2:11][CH3:12].ClC1C=CC(CO)=CC=1CCO>C(O)C>[CH2:11]([C:10]1[S:14][CH:2]=[C:3]([C:4]([O:6][CH2:7][CH3:8])=[O:5])[N:13]=1)[CH3:12]

Participants

5

Reactant 3

HCID 66144Ethyl bromopyruvateHCID 2760628PropanethioamideHCID 579893372-(2-Chloro-5-(hydroxymethyl)phenyl)ethanol

Product 1

HCID 15056276Ethyl 2-ethyl-1,3-thiazole-4-carboxylate

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

Ethyl 3-bromo-2-oxopropanoate (24.7 mL) was added dropwise over 10 min to a solution of propanethioamide [Carboxylic Acid 1, step a] (15.8 g) in ethanol (150 mL) at 0-10° C. under nitrogen. When the addition was complete the mixture was stirred at ambient temperature for 18 hours. The mixture was concentrated in vacuo, the residue diluted with water and extracted into ethyl acetate (×3). The combined extracts were washed with brine, dried over magnesium sulfate, filtered and the solvent removed. The crude product was purified by flash silica chromatography, elution gradient 10, 15 and 20% ethyl acetate in isohexane. Fractions containing the product were evaporated to dryness to afford the subtitled compound as a pale green solid. Yield 16.0 g.

Workup

  1. additionWhen the addition
  2. concentrationThe mixture was concentrated in vacuo
  3. additionthe residue diluted with water
  4. extractionextracted into ethyl acetate (×3)
  5. washThe combined extracts were washed with brine
  6. dry with materialdried over magnesium sulfate
  7. filtrationfiltered
  8. customthe solvent removed
  9. customThe crude product was purified by flash silica chromatography, elution gradient 10, 15 and 20% ethyl acetate in isohexane
  10. additionFractions containing the product
  11. customwere evaporated to dryness

Sources & evidence

ORD record
ord-6bf56635758548ac98369446656d35ab
Source dataset
uspto-grants-2013_07
Patent number
US08476265B2

Reaction notes

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