Sulfur Dioxide → 3-(4,8-Dimethylnona-3,7-dien-1-yl)-2,5-dihydro-1H-1lambda~6~-thiophene-1,1-dione

HRID 464050Notes

Reaction equation

HRID 464050 reaction equation
[CH3:1][CH2:2][C:3]([CH2:5][CH2:6]/[CH:7]=[C:8](/[CH2:10][CH2:11][CH:12]=[C:13]([CH3:15])[CH3:14])\[CH3:9])=[CH2:4].[S:16](=[O:18])=[O:17]>>[CH3:9][C:8]([CH2:10][CH2:11][CH:12]=[C:13]([CH3:14])[CH3:15])=[CH:7][CH2:6][CH2:5][C:3]1[CH2:4][S:16]([CH2:1][CH:2]=1)(=[O:18])=[O:17]

Participants

3

Reactant 2

HCID 1119Sulfur DioxideHCID 15228937beta Farnesene

Product 1

HCID 713378133-(4,8-Dimethylnona-3,7-dien-1-yl)-2,5-dihydro-1H-1lambda~6~-thiophene-1,1-dioneYield 58%

Procedure

The (E)-β-farnesene containing product of Example 1 (17 g) and liquid sulphur dioxide are sealed in a glass ampoule and stored at ambient temperature for 18 hours. The ampoule is opened after cooling and the excess SO2 is allowed to evaporate. The residue is then chromatographed on Florisil using sequentially hexane, an ether/hexane mixture of increasing concentration in ether, and finally ether, the effluent being monitored by n.m.r. Removal of the solvent under vacuum from the appropriate fractions gives 3-(4,8-dimethyl-3,7-nonadienyl) sulpholene (II) as a straw coloured liquid (9 g, 58%); nD20 1.5080; M+ (m/z as % of base peak): 268 (0.02); δ(CCl4) 1.70 (m, 9H), 2.08 (m, 8H), 3.70 (m, 4H), 5.16 (m, 2H), 5.78 (br, t, 1H). Note: On heating at 180° C. under a vacuum of 1τ the sulpholene regenerates an (E)- and (Z)-β-farnesene mixture in high yield.

Workup

  1. temperatureafter cooling
  2. customto evaporate
  3. customThe residue is then chromatographed on Florisil using sequentially hexane
  4. additionan ether/hexane mixture
  5. temperatureof increasing
  6. concentrationconcentration in ether
  7. customRemoval of the solvent under vacuum from the appropriate fractions

Sources & evidence

ORD record
ord-bc287d5b39c34e5188ef4a474866f87d
Source dataset
uspto-grants-1985_10
Patent number
US04546110

Reaction notes

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