Tetrabutylammonium Fluoride → 3-Ethyl-2-methylpyridine

HRID 1645620Notes

Reaction equation

HRID 1645620 reaction equation
[CH3:1][C:2]1[C:7]([C:8]#[C:9][Si](C)(C)C)=[CH:6][CH:5]=[CH:4][N:3]=1.[F-].C([N+](CCCC)(CCCC)CCCC)CCC>O1CCCC1>[CH2:8]([C:7]1[C:2]([CH3:1])=[N:3][CH:4]=[CH:5][CH:6]=1)[CH3:9]

Participants

4

Reactant 2

HCID 2724141Tetrabutylammonium FluorideHCID 597925602-Methyl-3-((trimethylsilyl)ethynyl)pyridine

Product 1

HCID 340873-Ethyl-2-methylpyridineYield 51.1%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

First, 2-methyl-3-((trimethylsilyl)ethynyl)pyridine (22.6 g, 119 mmol) was dissolved in tetrahydrofuran (dehydrated) (200 ml). To the mixture, tetrabutyl ammonium fluoride (1N tetrahydrofuran solution) (150 ml, 150 mmol) was added. The mixture was stirred at room temperature for one hour. The reaction mixture was partitioned by ethyl acetate and a saturated aqueous ammonium chloride solution. The aqueous layer was extracted with ethyl acetate. The organic layers were combined and washed twice with a saturated aqueous ammonium chloride solution, dried over anhydrous magnesium sulfate, and distilled by a rotary evaporator. To the obtained fraction, 10% palladium/carbon (900 mg) was added and stirred in a hydrogen atmosphere at room temperature for 2 hours. The reaction mixture was filtrated through anhydrous magnesium sulfate and cerite. To the filtrate, 10% palladium/carbon (810 mg) was added and the mixture was stirred in a hydrogen atmosphere at room temperature for 4 hours. The reaction mixture was filtrated through anhydrous magnesium sulfate and celite and thereafter the filtrate was concentrated to obtain the title compound (7.25 g, yield: 51.1%) as a colorless oil.

Workup

  1. customThe reaction mixture was partitioned by ethyl acetate
  2. extractionThe aqueous layer was extracted with ethyl acetate
  3. washwashed twice with a saturated aqueous ammonium chloride solution
  4. dry with materialdried over anhydrous magnesium sulfate
  5. distillationdistilled by a rotary evaporator
  6. additionTo the obtained fraction, 10% palladium/carbon (900 mg) was added
  7. stirringstirred in a hydrogen atmosphere at room temperature for 2 hours
  8. filtrationThe reaction mixture was filtrated through anhydrous magnesium sulfate
  9. additionTo the filtrate, 10% palladium/carbon (810 mg) was added
  10. stirringthe mixture was stirred in a hydrogen atmosphere at room temperature for 4 hours
  11. filtrationThe reaction mixture was filtrated through anhydrous magnesium sulfate and celite
  12. concentrationthe filtrate was concentrated

Sources & evidence

ORD record
ord-5da7751cdeca4b5a8c2972baeef02541
Source dataset
uspto-grants-2012_02
Patent number
US08124780B2

Reaction notes

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