Potassium Carbonate → Ethyl 2-[(2-amino-1,3-thiazol-5-yl)sulfanyl]-2-methylpropanoate

HRID 1363737Notes

Reaction equation

HRID 1363737 reaction equation
[S:1]([C:4]1[S:8][C:7]([NH2:9])=[N:6][CH:5]=1)C#N.C(S)[C@@H](O)[C@@H](O)CS.[CH2:18]([O:20][C:21](=[O:26])[C:22](Br)([CH3:24])[CH3:23])[CH3:19].C([O-])([O-])=O.[K+].[K+]>CO.CCOC(C)=O.O>[CH2:18]([O:20][C:21](=[O:26])[C:22]([S:1][C:4]1[S:8][C:7]([NH2:9])=[N:6][CH:5]=1)([CH3:24])[CH3:23])[CH3:19]

Participants

8

Reactant 4

HCID 11430Potassium CarbonateHCID 11745Propanoic acid, 2-bromo-2-methyl-, ethyl esterHCID 439352DithioerythritolHCID 3109677[(2-Amino-1,3-thiazol-5-yl)sulfanyl]formonitrile

Product 1

HCID 57481427Ethyl 2-[(2-amino-1,3-thiazol-5-yl)sulfanyl]-2-methylpropanoateYield 53.6%

Reagents, catalysts & solvents 3

HCID 887MethanolSolventHCID 962WaterSolventHCID 8857Ethyl AcetateSolvent

Procedure

In a nitrogen atmosphere 5-thiocyanato-thiazol-2-ylamine (10 g, 64 mmol) dissolved in MeOH (300 mL) was added 2,3-dihydroxy-1,4-dithiolbutane (DTT, 9.8 g, 64 mmol) and stirred at room temperature for 1½ h. Then 2-bromo-2-methyl-propionic acid ethyl ester (13.6 g, 70 mmol) and K2CO3 (10.5 g, 76 mmol) was added and the reaction mixture was stirred for further 13H. Addition of water (500 mL) and EtOAc (500 mL). Separation of the organic phase followed by extraction of the aqueous phase with EtOAc (2×300 mL). The combined organic phases were washed with water (500 mL) and brine (2×400 mL) and dried (MgSO4), filtered and evaporated. The crude product was dissolved in a small amount of DCM and purified by flash chromatography (heptane/EtOAc 2:1->1:2). Fractions containing the product were pooled and evaporated to a product containing impurities of DDT. This product was dissolved in diethyl ether (100 mL) and washed with water several times. The ether phase was dried (MgSO4), filtered and evaporated to give 8.45 g (54%) of 95% pure 2-(2-amino-thiazol-5-ylsulfanyl)-2-methyl-propionic acid ethyl ester as light brown crystals.

Workup

  1. stirringthe reaction mixture was stirred for further 13H
  2. customSeparation of the organic phase
  3. extractionfollowed by extraction of the aqueous phase with EtOAc (2×300 mL)
  4. washThe combined organic phases were washed with water (500 mL) and brine (2×400 mL)
  5. dry with materialdried (MgSO4)
  6. filtrationfiltered
  7. customevaporated
  8. dissolutionThe crude product was dissolved in a small amount of DCM
  9. custompurified by flash chromatography (heptane/EtOAc 2:1->1:2)
  10. additionFractions containing the product
  11. customevaporated to a product
  12. additioncontaining impurities of DDT
  13. dissolutionThis product was dissolved in diethyl ether (100 mL)
  14. washwashed with water several times
  15. dry with materialThe ether phase was dried (MgSO4)
  16. filtrationfiltered
  17. customevaporated

Sources & evidence

ORD record
ord-75c8e3cd5fe84b51a68381e41d9459e6
Source dataset
uspto-grants-2011_02
Patent number
US07884210B2

Reaction notes

Loading…