4'-Fluoroacetophenone → (4-Fluorophenyl)glyoxal

HRID 2086551Notes

Reaction equation

HRID 2086551 reaction equation
[Se](=O)=[O:2].[F:4][C:5]1[CH:10]=[CH:9][C:8]([C:11](=[O:13])[CH3:12])=[CH:7][CH:6]=1>O1CCOCC1>[F:4][C:5]1[CH:10]=[CH:9][C:8]([C:11]([CH:12]=[O:2])=[O:13])=[CH:7][CH:6]=1

Participants

4

Reactant 2

HCID 98284'-FluoroacetophenoneHCID 24007Selenium Dioxide

Product 1

HCID 101249(4-Fluorophenyl)glyoxalYield 79%

Reagents, catalysts & solvents 1

HCID 312751,4-DioxaneSolvent

Conditions

Temperature
50 °C

Procedure

Thus, 18.5 g of selenium dioxide was dissolved in 100 mL of dioxane by warming to 50° C. and stirring until all was in solution. To this solution was added. 23 g of 4′-fluoroacetophenone and the reaction was refluxed for 4 h. The hot solution was decanted from the solid selenium and the dioxane and water were removed by distillation through a short column at atmospheric pressure. Distillation of the residue at reduced pressure afforded 20 g of 4-fluorophenylglyoxal as a thick yellow oil which was contaminated by some starting 4′-fluoroacetophenone. This can be used directly or, more preferably, it can be converted to pure hydrate (see the last paragraph of the reference and note 5). A portion was boiled in water for 0.5 h and the aqueous layer was decanted from an oily residue and then allowed to cool. The hydrate is obtained as a white solid after filtration and air drying.

Workup

  1. additionTo this solution was added
  2. customThe hot solution was decanted from the solid selenium
  3. customthe dioxane and water were removed by distillation through a short column at atmospheric pressure
  4. distillationDistillation of the residue at reduced pressure

Sources & evidence

ORD record
ord-3bb0e4618a494d0eb5eb003ab256c1a4
Source dataset
uspto-grants-2004_04
Patent number
US06727244B2

Reaction notes

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