Water → t-Butyl 2-(2-amino-4-thiazolyl)-2-[(1-(2-(trimethylsilyl)ethoxycarbonyl)-1-methylethoxy]imino]-acetate

HRID 1906601Notes

Reaction equation

HRID 1906601 reaction equation
[NH2:1][C:2]1[S:3][CH:4]=[C:5](/[C:7](=[N:15]/[OH:16])/[C:8]([O:10][C:11]([CH3:14])([CH3:13])[CH3:12])=[O:9])[N:6]=1.Br[C:18]([CH3:29])([CH3:28])[C:19]([O:21][CH2:22][CH2:23][Si:24]([CH3:27])([CH3:26])[CH3:25])=[O:20].C(=O)([O-])[O-].[K+].[K+].O>CN(C)C=O>[NH2:1][C:2]1[S:3][CH:4]=[C:5]([C:7](=[N:15][O:16][C:18]([C:19]([O:21][CH2:22][CH2:23][Si:24]([CH3:27])([CH3:26])[CH3:25])=[O:20])([CH3:29])[CH3:28])[C:8]([O:10][C:11]([CH3:13])([CH3:12])[CH3:14])=[O:9])[N:6]=1

Participants

6

Reactant 4

HCID 962WaterHCID 11430Potassium CarbonateHCID 13826576tert-butyl 2-(2-amino-1,3-thiazol-4-yl)-2-(N-hydroxyimino)acetateHCID 15058060Propanoic acid, 2-bromo-2-methyl-, 2-(trimethylsilyl)ethyl ester

Product 1

HCID 74015565t-Butyl 2-(2-amino-4-thiazolyl)-2-[(1-(2-(trimethylsilyl)ethoxycarbonyl)-1-methylethoxy]imino]-acetateYield 65.3%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Conditions

Temperature
25 °C

Procedure

24.9 g (102 mmol) of t-butyl 2-(2-amino-4-thiazolyl)-2-(Z)-hydroxyimino-acetate are dissolved in 400 ml of dimethylformamide. After the addition of 54.7 g (205 mmol) of 2-(trimethylsilyl)ethyl 2-bromo-2-methylpropionate, followed by 56.6 g (410 mmol) of finely ground potassium carbonate, the mixture is stirred at 25° C. for 4 hours in a nitrogen atmosphere. After the addition of 3 l of water, the mixture is extracted with 1.5 l of ethyl acetate. The organic phase is washed twice with 1.5 l of water. The aqueous phase is extracted with 1.5 l of ethyl acetate. The combined ethyl acetate solutions are dried over sodium sulphate and evaporated to dryness. The product is purified by flash chromatography on silica gel [hexane/ethyl acetate (2:1)] and crystallized from methanol/water. There are obtained 28.6 g (65.3%) of t-butyl 2-(2-amino-4-thiazolyl)-2-[(1-(2-(trimethylsilyl)ethoxycarbonyl)-1-methylethoxy]imino]-acetate of melting point 83° C.

Workup

  1. extractionthe mixture is extracted with 1.5 l of ethyl acetate
  2. washThe organic phase is washed twice with 1.5 l of water
  3. extractionThe aqueous phase is extracted with 1.5 l of ethyl acetate
  4. dry with materialThe combined ethyl acetate solutions are dried over sodium sulphate
  5. customevaporated to dryness
  6. customThe product is purified by flash chromatography on silica gel [hexane/ethyl acetate (2:1)]
  7. customcrystallized from methanol/water

Sources & evidence

ORD record
ord-3d147380c33e43579829053f7a015d4c
Source dataset
uspto-grants-1987_03
Patent number
US04652651

Reaction notes

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