Methyl Benzoate → 1-Phenyl-2-pyrazin-2-yl ethanone

HRID 924949

Reaction equation

HRID 924949 reaction equation
C(NC(C)C)(C)C.[Li]CCCC.[CH3:13][C:14]1[CH:19]=[N:18][CH:17]=[CH:16][N:15]=1.[C:20](OC)(=[O:27])[C:21]1[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=1>C1COCC1>[C:21]1([C:20](=[O:27])[CH2:13][C:14]2[CH:19]=[N:18][CH:17]=[CH:16][N:15]=2)[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=1

Participants

6

Reactant 4

HCID 7150Methyl BenzoateHCID 7912DiisopropylamineHCID 79762-MethylpyrazineHCID 178418339Butyllithium

Product 1

HCID 5209771-Phenyl-2-pyrazin-2-yl ethanoneYield 33.3%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent3×

Procedure

To a mixture of diisopropyl-amine (1.29 g, 12.7 mmol) in anhydrous THF (10 mL) was added n-BuLi (2.5 M/L in hexane, 4.7 mL, 11.7 mmol) at −78° C., after being stirred for 30 minutes, a solution of 2-methylpyrazine (1 g, 10.6 mmol) in THF (5 mL) was added, and the mixture was stirred at −78° C. for 30 minutes, a solution of methyl benzoate (1.4 g, 10.6 mmol) in THF (5 mL) was added, and the mixture was stirred at this temperature for 3 hours. When TLC indicated that the starting material was consumed, the reaction mixture was diluted with EtOAc, and the mixture was washed with water and brine, and concentrated. The residue was purified by column chromatography (PE:EtOAc=30:1) to give Intermediate 26 (700 mg, yield 33.3%).

Workup

  1. stirringthe mixture was stirred at −78° C. for 30 minutes
  2. stirringthe mixture was stirred at this temperature for 3 hours
  3. customwas consumed
  4. additionthe reaction mixture was diluted with EtOAc
  5. washthe mixture was washed with water and brine
  6. concentrationconcentrated
  7. customThe residue was purified by column chromatography (PE:EtOAc=30:1)

Sources & evidence

ORD record
ord-c5a759b4d1374a8c838f7d6bfdea1b4a
Source dataset
uspto-grants-2016_03
Patent number
US09283229B2

Linked notes

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