1,2-Dimethoxyethane → 2,2,2-Trifluoro-1-(pyrazin-2-yl)ethan-1-one

HRID 424961Notes

Reaction equation

HRID 424961 reaction equation
CO[C:3]([C:5]1[CH:10]=[N:9][CH:8]=[CH:7][N:6]=1)=[O:4].C(COC)OC.C[Si]([C:21]([F:24])([F:23])[F:22])(C)C.[F-].[Cs+]>CCCCCC.ClCCl>[F:22][C:21]([F:24])([F:23])[C:3]([C:5]1[CH:10]=[N:9][CH:8]=[CH:7][N:6]=1)=[O:4]

Participants

7

Reactant 4

HCID 80711,2-DimethoxyethaneHCID 25953Cesium fluorideHCID 72662Methyl pyrazinoateHCID 552549(Trifluoromethyl)trimethylsilane

Product 1

HCID 579305272,2,2-Trifluoro-1-(pyrazin-2-yl)ethan-1-one

Reagents, catalysts & solvents 2

HCID 6344DichloromethaneSolventHCID 8058HexaneSolvent

Procedure

A solution of pyrazine carboxylate methyl ester is dissolved in an inert solvent, for example monoglyme (dimethoxyethane). To this solution is added a mixture of trimethylsilyltrifluoromethane and dry caesium fluoride. After about 12-24 hours, at a temperature of about room temperature, the solvent is removed under reduced pressure. The residue is dissolved in a mixture of an inert solvent, for example tetrahydrofuran, and an organic acid, for example acetic acid, and the mixture is treated with tert-butylammonium fluoride. The reaction is conducted at a temperature of about room temperature for about 3 hours. When the reaction is substantially complete, the compound of formula (18) is isolated by conventional means, for example by diluting with water, extracting the product into an inert solvent, for example ethyl acetate, washing with a solution of a mild inorganic base, for example sodium bicarbonate, and drying. Removal of the solvent under reduced pressure provides a crude compound, which can be purified by trituration with an inert solvent, for example a mixture of dichloromethane and hexane, to give a compound of formula (18), 2,2,2-trifluoro-1-(pyrazin-2-yl)ethanone.

Workup

  1. additionTo this solution is added
  2. customat a temperature of about room temperature, the solvent is removed under reduced pressure
  3. waitThe reaction is conducted at a temperature of about room temperature for about 3 hours
  4. additionby diluting with water
  5. extractionextracting the product into an inert solvent
  6. customdrying
  7. customRemoval of the solvent under reduced pressure
  8. customprovides a crude compound, which

Sources & evidence

ORD record
ord-99a95e9edf4747a484f87a942635fd62
Source dataset
uspto-grants-2012_01
Patent number
US08106059B2

Reaction notes

Loading…