Cyclohexanone → HCID 13882253, compound

HRID 979534Notes

Reaction equation

HRID 979534 reaction equation
Br[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][C:3]=1[F:8].C([Li])CCC.[C:14]1(=O)[CH2:19][CH2:18][CH2:17][CH2:16][CH2:15]1>O1CCCC1>[F:8][C:3]1[CH:4]=[CH:5][CH:6]=[CH:7][C:2]=1[C:14]1[CH2:19][CH2:18][CH2:17][CH2:16][CH:15]=1

Participants

5

Reactant 3

HCID 7967CyclohexanoneHCID 612591-Bromo-2-fluorobenzeneHCID 178418339Butyllithium

Product 1

HCID 13882253HCID 13882253, compoundYield 53%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

A solution of o-bromofluorobenzene (17.5 g; 0.10 mole) in 150 ml of dry tetrahydrofuran (THF) was chilled to -60° and n-butyllithium (50 ml of 2.4M; 0.12 mole) was added dropwise at a rate such that the reaction temperature did not rise above -55°. When the addition was complete a solution of cyclohexanone (10.0 g; 0.10 mole) in 50 ml of THF was added, again maintaining the reaction temperature below -55°. The reaction was then allowed to come to room temperature over 90 minutes and was quenched by the addition of 10 ml of saturated NH4Cl solution. An additional 400 ml of water was added, then the organic layer was separated and dried. The aqueous phase was extracted again with ethyl acetate, then the combined, dried, organic phases were concentrated to an oil. This oil was dissolved in 200 ml of glacial acetic acid and treated with 1 ml of concentrated H2SO4. The acetic acid was concentrated to about 30 ml on a rotary evaporator, then diluted with 250 ml of water and the solution made basic with 50% NaOH. Extraction with ether, followed by drying and concentration under reduced pressure gave an oil that was distilled at 0.15 mm to give 9.26 g (53%) of 1-(2-fluorophenyl)cyclohexene, b.p. 70°-72°, that was homogeneous to thin layer chromatography (TLC).

Workup

  1. customdid not rise above -55°
  2. additionWhen the addition
  3. additionwas added
  4. temperatureagain maintaining the reaction temperature below -55°
  5. customwas quenched by the addition of 10 ml of saturated NH4Cl solution
  6. additionAn additional 400 ml of water was added
  7. customthe organic layer was separated
  8. customdried
  9. extractionThe aqueous phase was extracted again with ethyl acetate
  10. customdried
  11. concentrationorganic phases were concentrated to an oil
  12. dissolutionThis oil was dissolved in 200 ml of glacial acetic acid
  13. additiontreated with 1 ml of concentrated H2SO4
  14. concentrationThe acetic acid was concentrated to about 30 ml on a rotary evaporator
  15. additiondiluted with 250 ml of water
  16. extractionExtraction with ether
  17. customby drying
  18. concentrationconcentration under reduced pressure
  19. customgave an oil that
  20. distillationwas distilled at 0.15 mm

Sources & evidence

ORD record
ord-8d02103782be4341b651193cf8af9434
Source dataset
uspto-grants-1987_05
Patent number
US04668690

Reaction notes

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