Water → Tert-butyl 2-methoxyimino-3-oxobutyrate

HRID 2081326Notes

Reaction equation

HRID 2081326 reaction equation
[OH:1][N:2]=[C:3]([C:11](=[O:13])[CH3:12])[C:4]([O:6][C:7]([CH3:10])([CH3:9])[CH3:8])=[O:5].O.[OH-].[Na+].S(OC)(O[CH3:21])(=O)=O>C(Cl)Cl>[CH3:21][O:1][N:2]=[C:3]([C:11](=[O:13])[CH3:12])[C:4]([O:6][C:7]([CH3:9])([CH3:8])[CH3:10])=[O:5]

Participants

6

Reactant 4

HCID 962WaterHCID 6497Dimethyl SulfateHCID 14798Sodium Hydroxide2×HCID 178468384tert-butyl 2-hydroxyimino-3-oxobutanoate

Product 1

HCID 54110352Tert-butyl 2-methoxyimino-3-oxobutyrateYield 93.3%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

To the tert-butyl 2-hydroxyimino-3-oxobutyrate was added water [6 l ], to which was added 30% sodium hydroxide [800 ml] at 28° C. while stirring to render the pH to 9.0. To the resultant solution was added dimethyl sulfate [1324 g] at 28° to 30° C. in the course of 20 minutes, which was stirred for 4 hours while adding thereto at 25° to 30° C. a 30% aqueous solution of sodium hydroxide [500 ml] to adjust the pH within the range of 8.7 to 9.0. After completion of the reaction, extraction was conducted with methylene chloride [4 l ], and the aqueous layer was subjected to further extraction with methylene chloride [2 l ]. The methylene chloride layers were combined and washed with a 1N aqueous solution of sodium hydroxide, 1N HCl, a 5% aqueous solution of sodium hydrogencarbonate and water, each one litre portion, successively. The resultant solution was dried over anhydrous sodium sulfate [700 g], followed by concentration under reduced pressure to obtain tert-butyl 2-methoxyimino-3-oxobutyrate [1878 g] as an oily product. The yield was 93.3%.

Workup

  1. stirringwas stirred for 4 hours
  2. additionwhile adding
  3. customat 25° to 30° C.
  4. customAfter completion of the reaction, extraction
  5. extractionthe aqueous layer was subjected to further extraction with methylene chloride [2 l ]
  6. washwashed with a 1N aqueous solution of sodium hydroxide, 1N HCl
  7. dry with materialThe resultant solution was dried over anhydrous sodium sulfate [700 g]
  8. concentrationfollowed by concentration under reduced pressure

Sources & evidence

ORD record
ord-3da42c6b0d884d68a905f376d9f126aa
Source dataset
uspto-grants-1993_02
Patent number
US05183929

Reaction notes

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