Tert-butyl acetoacetate → tert-butyl 2-hydroxyimino-3-oxobutanoate

HRID 1062432Notes

Reaction equation

HRID 1062432 reaction equation
[C:1]([O:7][C:8]([CH3:11])([CH3:10])[CH3:9])(=[O:6])[CH2:2][C:3]([CH3:5])=[O:4].[N:12]([O-])=[O:13].[Na+]>C(O)(=O)C.O>[OH:13][N:12]=[C:2]([C:3](=[O:4])[CH3:5])[C:1]([O:7][C:8]([CH3:11])([CH3:10])[CH3:9])=[O:6]

Participants

5

Reactant 2

HCID 15538Tert-butyl acetoacetateHCID 23668193Sodium Nitrite

Product 1

HCID 178468384tert-butyl 2-hydroxyimino-3-oxobutanoateYield 93.3%

Reagents, catalysts & solvents 2

HCID 176Acetic AcidSolventHCID 962WaterSolvent2×

Procedure

t-Butyl acetoacetate (5.0 g, 31.6 mmol) was dissolved in acetic acid (4.5 mL), cooled by an ice water bath, and treated with sodium nitrite (2.45 g, 35.5 mmol) in water (5.5 mL) while the internal temperature was kept at <10° C. (see, e.g., U.S. Pat. No. 4,743,586). After the addition was complete, the mixture was stirred at rt for 30 minutes before water (16 mL) was added. After 2 h, extraction with ether (3×25 mL), which was washed with water (10 mL), sodium bicarbonate solution (3×10 mL), and water (20 mL), gave t-butyl 2-hydroxyimino-3-oxobutanoate as a white solid (5.52 g, 93%): 1H NMR (300 MHz, CDCl3) δ 8.61 (s, 1H), 2.39 (s, 3H), 1.58 (s, 9H).

Workup

  1. temperaturecooled by an ice water bath
  2. customwas kept at <10° C.
  3. additionAfter the addition
  4. additionwas added
  5. extractionextraction with ether (3×25 mL), which
  6. washwas washed with water (10 mL), sodium bicarbonate solution (3×10 mL), and water (20 mL)

Sources & evidence

ORD record
ord-d1c9a190241342379efca1cd6342b444
Source dataset
uspto-grants-2005_11
Patent number
US06960601B2

Reaction notes

Loading…