Ethyl chloroformate → Ethyl 3-(4-methylphenyl)-3-oxopropanoate

HRID 2211591Notes

Reaction equation

HRID 2211591 reaction equation
[CH3:1][Si]([N-][Si](C)(C)C)(C)C.[Li+].[CH3:11][C:12]([C:14]1[CH:19]=[CH:18][C:17](SC)=[CH:16][CH:15]=1)=[O:13].[CH2:22]([O:24][C:25](Cl)=[O:26])[CH3:23]>O1CCCC1>[CH2:22]([O:24][C:25](=[O:26])[CH2:11][C:12](=[O:13])[C:14]1[CH:19]=[CH:18][C:17]([CH3:1])=[CH:16][CH:15]=1)[CH3:23]

Participants

5

Reactant 3

HCID 10928Ethyl chloroformateHCID 745011-(4-(Methylthio)phenyl)ethan-1-oneHCID 2733832Lithium Hexamethyldisilazide

Product 1

HCID 292637Ethyl 3-(4-methylphenyl)-3-oxopropanoateYield 65.9%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

Lithium bis(trimethylsilyl)amide (20% in tetrahydrofuran, 203.6 ml, 217 mmol) was added dropwise to a stirred solution of 4-methylthioacetophenone (20.2 g, 121 mmol) in dried tetrahydrofuran (300 ml) at −20° C. and stirring was continued for 1 hour at −20° C. Ethylchloroformate (19.8 g, 182 mmol) was added dropwise to the stirred reaction mixture at −20° C. and stirring was continued for 3 hours. The reaction was quenched with saturated ammonium chloride solution and extracted with ethylacetate. The organic extract was washed with water, brine, dried over anhydrous sodium sulphate and concentrated to dryness in vacuum. The crude product thus obtained was purified by column chromatography to yield the title compound as viscous oil (16.45 g, 56.8%). 1H-NMR (DMSO-d6): δ 1.15–1.19 (t, 3H), 2.54 (s, 3H), 4.07–4.11 (q, 2H), 4.13 (s, 2H), 7.36–7.39 (d, 2H), 7.85–7.88 (d, 2H). MS m/z: 239 (M+). Preparation 4 Synthesis of 2-amino-6-(4-methylphenyl)-1,3-oxazin-4-one

Workup

  1. stirringstirring
  2. waitwas continued for 3 hours
  3. customThe reaction was quenched with saturated ammonium chloride solution
  4. extractionextracted with ethylacetate
  5. extractionThe organic extract
  6. washwas washed with water, brine
  7. dry with materialdried over anhydrous sodium sulphate
  8. concentrationconcentrated to dryness in vacuum
  9. customThe crude product thus obtained
  10. customwas purified by column chromatography

Sources & evidence

ORD record
ord-204fe06291e249eea4af6a79de98ae83
Source dataset
uspto-grants-2006_09
Patent number
US07101873B2

Reaction notes

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