Water → 1-Ethynylcyclohexene

HRID 371962Notes

Reaction equation

HRID 371962 reaction equation
[C:1]([C:3]1[CH2:8][CH2:7][CH2:6][CH2:5][CH:4]=1)#[CH:2].[H-].[Na+].[CH3:11][CH:12]1[CH:17]([CH3:18])[CH2:16][CH2:15][CH:14]([CH3:19])[C:13]1=[O:20].O>O1CCCC1.CCOCC>[C:1]([C:3]1[CH2:8][CH2:7][CH2:6][CH2:5][CH:4]=1)#[CH:2].[CH3:11][CH:12]1[CH:17]([CH3:18])[CH2:16][CH2:15][CH:14]([CH3:19])[C:13]1([C:2]#[C:1][C:3]1[CH2:8][CH2:7][CH2:6][CH2:5][CH:4]=1)[OH:20]

Participants

8

Reactant 4

HCID 962WaterHCID 24758Sodium hydrideHCID 791281-EthynylcyclohexeneHCID 1425832,3,6-Trimethylcyclohexan-1-one

Product 2

HCID 791281-EthynylcyclohexeneHCID 203524611-(2,3,6-Trimethyl-1-hydroxy-cyclohexyl)-2-(cyclohex-1-en-1-yl)-acetylene

Reagents, catalysts & solvents 2

HCID 3283Diethyl EtherSolventHCID 8028TetrahydrofuranSolvent

Procedure

21.5 g of ethynylcyclohexene are added dropwise to a suspension of 6 g of 80% strength sodium hydride in 200 ml of tetrahydrofuran under reflux, and the reaction mixture is kept under reflux conditions until no further gas is evolved. 28 g of 2,3,6-trimethyl-cyclohexanone are then added dropwise at room temperature and the mixture is left overnight, whilst being stirred, in order to complete the reaction. Water is added to the reaction mixture, the reaction product is taken up in ether and the ether solution is washed with water, dried and concentrated. Fractional distillation gives 9 g of unconverted ethynylcyclohexene, 8 g of starting ketone, and 22 g of 1-(2,3,6-trimethyl-1-hydroxy-cyclohexyl)-2-(cyclohex-1-en-1-yl)-acetylene of boiling point 120° C/0.1 mm Hg and refractive index nD25 = 1.5143. This corresponds to a yield of 68% of theory, based on trimethylcyclohexanone converted. Fragrance note: faint, tart, herbaceous.

Workup

  1. temperatureunder reflux
  2. customthe reaction
  3. washthe ether solution is washed with water
  4. customdried
  5. concentrationconcentrated
  6. distillationFractional distillation

Sources & evidence

ORD record
ord-c49b3e6afff64eb6bb4958e2c9f6e8a1
Source dataset
uspto-grants-1978_05
Patent number
US04088681

Reaction notes

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