2-Oxime 2,3-butanedione → HCID 23076346, compound

HRID 2221632Notes

Reaction equation

HRID 2221632 reaction equation
[CH:1]([C:3]1[CH:4]=[CH:5][C:6]([CH3:13])=[C:7]([CH:12]=1)[C:8]([O:10][CH3:11])=[O:9])=[O:2].[CH3:14][C:15](=[N:19]O)[C:16](=O)[CH3:17].[ClH:21].C(OCC)(=O)C>>[Cl:21][CH2:14][C:15]1[N:19]=[C:1]([C:3]2[CH:4]=[CH:5][C:6]([CH3:13])=[C:7]([CH:12]=2)[C:8]([O:10][CH3:11])=[O:9])[O:2][C:16]=1[CH3:17]

Participants

4

Reactant 3

HCID 63989692-Oxime 2,3-butanedioneHCID 19700886Methyl 5-formyl-2-methylbenzoateHCID 21866389Hydrogen chloride-ethyl acetate

Product 1

HCID 23076346HCID 23076346, compoundYield 41%

Procedure

A mixture of methyl 5-formyl-2-methylbenzoate (2.10 g), 2,3-butanedione-2-oxime (1.19 g) and 4N hydrogenchloride-ethyl acetate (50 mL) was stirred at room temperature for 3 days. The reaction mixture was concentrated, diethyl ether was added to the residue to allow precipitation of crystals, and crystals were collected by filtration. A mixture of the obtained crystal, tetrahydrofuran (50 mL) and thionyl chloride (2.11 g) was heated under reflux for 2 hrs. The reaction mixture was concentrated and ethyl acetate was added to the residue. The ethyl acetate layer was washed successively with saturated aqueous sodium hydrogen carbonate solution and saturated brine, dried over anhydrous magnesium sulfate and concentrated. The obtained residue was subjected to silica gel column chromatography to give methyl 5-(4-chloromethyl-5-methyl-1,3-oxazol-2-yl)-2-methylbenzoate as colorless crystals (1.34 g, yield 41%) from a fraction eluted with ethyl acetate-hexane (1:9, v/v). Recrystallization from ethyl acetate-hexane gave colorless prism crystals. melting point: 89-90° C.

Workup

  1. concentrationThe reaction mixture was concentrated
  2. additiondiethyl ether was added to the residue
  3. customprecipitation of crystals, and crystals
  4. filtrationwere collected by filtration
  5. additionA mixture of the obtained crystal, tetrahydrofuran (50 mL) and thionyl chloride (2.11 g)
  6. temperaturewas heated
  7. temperatureunder reflux for 2 hrs
  8. concentrationThe reaction mixture was concentrated
  9. additionethyl acetate was added to the residue
  10. washThe ethyl acetate layer was washed successively with saturated aqueous sodium hydrogen carbonate solution and saturated brine
  11. dry with materialdried over anhydrous magnesium sulfate
  12. concentrationconcentrated

Sources & evidence

ORD record
ord-f92ae9069d7146f892ced36c04bc8405
Source dataset
uspto-grants-2008_05
Patent number
US07368578B2

Reaction notes

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