Dimethyl oxalate → Methyl 4-(3-pyridazinyl)-2,4-dioxobutanoate

HRID 1437272Notes

Reaction equation

HRID 1437272 reaction equation
C[Si]([N-][Si](C)(C)C)(C)C.[Li+].[C:11]([C:14]1[N:15]=[N:16][CH:17]=[CH:18][CH:19]=1)(=[O:13])[CH3:12].[C:20](OC)(=[O:25])[C:21]([O:23][CH3:24])=[O:22]>O1CCCC1>[CH3:24][O:23][C:21](=[O:22])[C:20](=[O:25])[CH2:12][C:11]([C:14]1[N:15]=[N:16][CH:17]=[CH:18][CH:19]=1)=[O:13]

Participants

5

Conditions

Temperature
-78 °C

Procedure

In an argon atmosphere and while cooling at −78° C., 1.0M lithium bis(trimethylsilyl)amide in tetrahydrofuran (19 mL) was added dropwise to 3-acetylpyridazine (2.097 g) in tetrahydrofuran (50 mL), followed by stirring for 1 hour. To the reaction mixture, dimethyl oxalate (4.055 g) in tetrahydrofuran (35 mL) was added dropwise, and the resultant mixture was stirred at 0° C. for 2 hours. The reaction solvent was removed under reduced pressure. Water was added to the residue, and the mixture was washed with diethyl ether. The aqueous layer was slightly acidified with aqueous 1N hydrochloric acid, and extracted with ethyl acetate. The organic layer was dried over sodium sulfate anhydrate, followed by filtration. The solvent was removed under reduced pressure, to thereby give 4-(3-pyridazinyl)-2,4-dioxobutanoic acid methyl ester as a solid (2.63 g, 73%).

Workup

  1. customThe reaction solvent was removed under reduced pressure
  2. additionWater was added to the residue
  3. washthe mixture was washed with diethyl ether
  4. extractionextracted with ethyl acetate
  5. dry with materialThe organic layer was dried over sodium sulfate anhydrate
  6. filtrationfollowed by filtration
  7. customThe solvent was removed under reduced pressure

Sources & evidence

ORD record
ord-52ac3b00bd124d8591cbb77b5f1e72c0
Source dataset
uspto-grants-2009_11
Patent number
US07622471B2

Reaction notes

Loading…