p-Toluenesulfonic acid → 2,2,4-Trimethyl-4-(2,2,3-trimethylcyclopent-3-en-1-yl)tetrahydrofuran

HRID 1377437Notes

Reaction equation

HRID 1377437 reaction equation
[CH3:1][C:2]1([CH3:16])[C:6]([CH3:7])=[CH:5][CH2:4][CH:3]1[C:8]([CH3:15])([CH2:11][C:12]([CH3:14])=[CH2:13])[CH2:9][OH:10].CC1C=CC(S(O)(=O)=O)=CC=1>CCCCCCC>[CH3:13][C:12]1([CH3:14])[CH2:11][C:8]([CH3:15])([CH:3]2[CH2:4][CH:5]=[C:6]([CH3:7])[C:2]2([CH3:16])[CH3:1])[CH2:9][O:10]1

Participants

4

Reactant 2

HCID 6101p-Toluenesulfonic acidHCID 229140992-(2,2,3-Trimethylcyclopent-3-en-1-yl)-2,4-dimethyl-4-pentenol

Product 1

HCID 229141012,2,4-Trimethyl-4-(2,2,3-trimethylcyclopent-3-en-1-yl)tetrahydrofuranYield 96.8%

Reagents, catalysts & solvents 1

HCID 8900HeptaneSolvent

Procedure

A 1 liter 3 neck round bottomed flask was charged with 600 ml of heptane, 155.3 g of 2-(2,2,3-trimethylcyclopent-3-en-1-yl)-2,4-dimethyl-4-pentenol at 97.7% (0.68 mole) and 0.9 g of p-TSA. The batch was refluxed under nitrogen for 26 hours. Then batch was cooled and washed with 500 ml of 10% sodium carbonate, 500 ml of water and 500 ml of brine. The batch was dried with magnesium sulfate, filtered, and concentrated in vacuo to afford 163.3 g of crude product. Distillation of the product afforded 150.3 g of purified product (92.7%). BP 84° C./0.5 mmHg; 1H-NMR (300 MHz), δ 0.92 (3H, s), 1.10 (3H, s), 1.20 (3H, s), 1.25 (3H, s), 1.33 (3H, s), 1.55 (4H, sharp m), 1.81-1.99 (2H, m), 2.16 (2H, br m), 3.60 (2H, AB quintet J=8.7 Hz), 5.24 (1H, s); 13C-NMR (75 MHz), δ 12.35, 22.03, 24.57, 25.66, 28.69, 29.96, 32.48, 47.38, 48.36, 50.58, 57.22, 77.63, 80.60, 121.20, 148.01; IR (Neat), 3020, 2980, 1450, 1060 cm-1 ; MS (m/e), 222 (M+), 207, 191, 95, 43;

Workup

  1. temperatureThe batch was refluxed under nitrogen for 26 hours
  2. temperatureThen batch was cooled
  3. washwashed with 500 ml of 10% sodium carbonate, 500 ml of water and 500 ml of brine
  4. dry with materialThe batch was dried with magnesium sulfate
  5. filtrationfiltered
  6. concentrationconcentrated in vacuo
  7. customto afford 163.3 g of crude product
  8. distillationDistillation of the product

Sources & evidence

ORD record
ord-5cdd9a0088724b1f8355838137b16aa1
Source dataset
uspto-grants-1997_09
Patent number
US05665696

Reaction notes

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