Potassium Carbonate → 2-Amino-4-methyl-5-(2-pyridylthio)thiazole

HRID 2380628Notes

Reaction equation

HRID 2380628 reaction equation
Cl.[NH2:2][C:3]1[S:4][C:5](Br)=[C:6]([CH3:8])[N:7]=1.[SH:10][C:11]1[CH:16]=[CH:15][CH:14]=[CH:13][N:12]=1.C(=O)([O-])[O-].[K+].[K+]>CN(C)C=O>[NH2:2][C:3]1[S:4][C:5]([S:10][C:11]2[CH:16]=[CH:15][CH:14]=[CH:13][N:12]=2)=[C:6]([CH3:8])[N:7]=1

Participants

5

Reactant 3

HCID 11430Potassium CarbonateHCID 189547282-Amino-5-bromo-4-methyl-1,3-thiazole hydrochlorideHCID 178418616HCID 178418616, compound

Product 1

HCID 189547352-Amino-4-methyl-5-(2-pyridylthio)thiazoleYield 48%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Conditions

Temperature
90 °C

Procedure

A mixture of 2-amino-5-bromo-4-methylthiazole hydrochloride (4.5 g), 2-mercaptopyridine (2.3 g) and potassium carbonate (7.0 g) in N,N-dimethylformamide (100 ml) was heated at 90° C. for 3 hours with stirring. The reaction mixture was concentrated under reduced pressure and water was added to this residue. The mixture was extracted with a mixture of tetrahydrofuran and ethyl acetate, washed with aqueous saturated sodium chloride and dried over magnesium sulfate. The solvent was concentrated under reduced pressure to give solid. The solid was subjected to column chromatography on silica gel (silica gel 60, 70-230 mesh; Merck: 300 g) and eluted with a mixture of chloroform and methanol (10:1). The fractions containing the objective compound were combined and concentrated under reduced pressure to give oil. Again the oil was subjected to column chromatography on silica gel (silica gel 60, 70-230 mesh; Merck: 200 g) and eluted with a mixture of dichloromethane and acetone (5:1). The fractions containing the objective compound were combined and concentrated under reduced pressure to give 2-amino-4-methyl-5-(2-pyridylthio)thiazole (2.1 g, yield: 47.9%).

Workup

  1. concentrationThe reaction mixture was concentrated under reduced pressure and water
  2. additionwas added to this residue
  3. extractionThe mixture was extracted with a mixture of tetrahydrofuran and ethyl acetate
  4. washwashed with aqueous saturated sodium chloride
  5. dry with materialdried over magnesium sulfate
  6. concentrationThe solvent was concentrated under reduced pressure
  7. customto give solid
  8. washeluted with a mixture of chloroform and methanol (10:1)
  9. additionThe fractions containing the objective compound
  10. concentrationconcentrated under reduced pressure
  11. customto give oil
  12. washeluted with a mixture of dichloromethane and acetone (5:1)
  13. additionThe fractions containing the objective compound
  14. concentrationconcentrated under reduced pressure

Sources & evidence

ORD record
ord-d50d9767591e4e9ebe7d18131b2ca2c2
Source dataset
uspto-grants-1994_11
Patent number
US05369107

Reaction notes

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