Water → (Z)-2-Methoxyimino-3-oxobutyric acid, 1,1-dimethylethyl ester

HRID 1462043Notes

Reaction equation

HRID 1462043 reaction equation
[C:1]([O:5][C:6](=[O:13])/[C:7](=[N:11]\[OH:12])/[C:8](=[O:10])[CH3:9])([CH3:4])([CH3:3])[CH3:2].[C:14](=O)([O-])[O-].[K+].[K+].S(OC)(OC)(=O)=O.O>CC(C)=O>[C:1]([O:5][C:6](=[O:13])/[C:7](=[N:11]\[O:12][CH3:14])/[C:8](=[O:10])[CH3:9])([CH3:2])([CH3:3])[CH3:4]

Participants

6

Conditions

Temperature
5 °C

Procedure

626.65 g of (Z)-2-hydroxyimino-3-oxo-butyric acid tert.butyl ester are dissolved in 2.86 l of acetone. The solution is cooled to 5° C. and treated portionwise with 703.5 g of potassium carbonate. 322 ml of dimethyl sulphate are then added dropwise to the yellow suspension without cooling during 1 hour, whereby the temperature of the mixture should not rise above 25° C. The light beige suspension is stirred at 20°-25° C. for about 4 hours until starting material can no longer be detected by thin-layer chromatography. Thereafter, the mixture is poured into 7 l of water and extracted three times with 1 l of ethyl acetate each time. The combined ethyl acetate extracts are washed three times with 1 l of water each time, dried over sodium sulphate and evaporated in vacuo at 40° C. The residual yellow oil is dried for a further 6 hours in a high vacuum at 40° C. and subsequently distilled. There is obtained (Z)-2methoxyimino-3-oxo-butyric acid tert.butyl ester as a yellow oil with a boiling point of 57° C. at 0.02 mmHg.

Workup

  1. temperaturewithout cooling during 1 hour
  2. customrise above 25° C
  3. extractionextracted three times with 1 l of ethyl acetate each time
  4. washThe combined ethyl acetate extracts are washed three times with 1 l of water each time
  5. dry with materialdried over sodium sulphate
  6. customevaporated in vacuo at 40° C
  7. customThe residual yellow oil is dried for a further 6 hours in a high vacuum at 40° C.
  8. distillationsubsequently distilled

Sources & evidence

ORD record
ord-d0c486bce5fd4337b5ddd244155cded6
Source dataset
uspto-grants-1984_07
Patent number
US04458072

Reaction notes

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