Ethyl thiooxamate → Ethyl 4-isopropylthiazole-2-carboxylate

HRID 1815712Notes

Reaction equation

HRID 1815712 reaction equation
Br[CH2:2][C:3](=O)[CH:4]([CH3:6])[CH3:5].[CH3:8][CH2:9][O:10][C:11]([C:13]([NH2:15])=[S:14])=[O:12]>>[CH2:9]([O:10][C:11]([C:13]1[S:14][CH:2]=[C:3]([CH:4]([CH3:6])[CH3:5])[N:15]=1)=[O:12])[CH3:8]

Participants

3

Reactant 2

HCID 2733398Ethyl thiooxamateHCID 108990371-Bromo-3-methylbutan-2-one

Product 1

HCID 10821861Ethyl 4-isopropylthiazole-2-carboxylateYield 50.2%

Procedure

A neat solution of 5.58 g (34 mmol) of 1-Bromo-3-methyl-butan-2-one and 4.50 g (34 mmol) of ethyl thioxamate (Aldrich) was heated at 70° C. over 18 h and then cooled to room temperature. The mixture was partitioned between sat. aqueous NaHCO3 and EtOAc, the EtOAc layer dried (MgSO4), concentrated and chromatographed over SiO2 (eluted with 2% to 40% EtOAc/hexanes) to afford 3.4 g (48% overall) of 4-isopropylthiazole-2-carboxylic acid ethyl ester as an oil: 1H NMR (500 MHz, CDCl3) δ ppm 1.32 (d, J=7 Hz, 6H), 1.42 (t, J=7.2 Hz, 3H), 3.23 (m, 1H), 4.46 (q, J=7.2 Hz, 2H), 7.18 (s, 1H).

Workup

  1. customThe mixture was partitioned between sat. aqueous NaHCO3 and EtOAc
  2. dry with materialthe EtOAc layer dried (MgSO4)
  3. concentrationconcentrated
  4. customchromatographed over SiO2 (eluted with 2% to 40% EtOAc/hexanes)

Sources & evidence

ORD record
ord-8142807cddd4444f88e0c1a46201ef5c
Source dataset
uspto-grants-2005_04
Patent number
US06878722B2

Reaction notes

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