Dimethyl Sulfoxide → Stilbene

HRID 2081765Notes

Reaction equation

HRID 2081765 reaction equation
[H-].[Na+].CS(C)=O.[PH4+].FC([C:12]1[CH:19]=[CH:18][CH:17]=[CH:16][C:13]=1[CH:14]=O)(F)F>C(OCC)(=O)C>[C:13]1([CH:14]=[CH:14][C:13]2[CH:12]=[CH:19][CH:18]=[CH:17][CH:16]=2)[CH:12]=[CH:19][CH:18]=[CH:17][CH:16]=1

Participants

6

Reactant 4

HCID 679Dimethyl SulfoxideHCID 24758Sodium hydrideHCID 123067o-(Trifluoromethyl)benzaldehydeHCID 5460504Phosphonium

Product 1

HCID 11502StilbeneYield 208.2%

Reagents, catalysts & solvents 1

HCID 8857Ethyl AcetateSolvent

Conditions

Temperature
80 °C

Procedure

In a nitrogen atmosphere, 8.7 g of 55% sodium hydride dispersion are added to 100 ml of absolute dimethylsulphoxide and stirred at 80° C. for 45 minutes. After cooling to ambient temperature, a suspension of 98 g (0.2 mol) of phosphonium salt 4 is added dropwise and the reaction mixture is stirred for a further 10 minutes. Then 34.8 g of trifluoromethylbenzaldehyde are added dropwise and the mixture is stirred for 2 hours at ambient temperature. The mixture is then diluted with 400 ml of ethyl acetate and washed twice with water. The organic phase is dried and the residue is chromatographed (SiO2 column, eluant: dichloromethane). The main fraction is evaporated down in vacuo and the residue is recrystallised from isopropylether. 37.5 g (61% of theory) of stilbene of the type 8 are obtained in the form of crystals, m.p. 157°-158° C.

Workup

  1. temperatureAfter cooling to ambient temperature
  2. additionis added dropwise
  3. stirringthe reaction mixture is stirred for a further 10 minutes
  4. stirringthe mixture is stirred for 2 hours at ambient temperature
  5. washwashed twice with water
  6. customThe organic phase is dried
  7. customthe residue is chromatographed (SiO2 column, eluant: dichloromethane)
  8. customThe main fraction is evaporated down in vacuo
  9. customthe residue is recrystallised from isopropylether

Sources & evidence

ORD record
ord-8cec91e2d88c4e74a3c11e3f5776a78f
Source dataset
uspto-grants-1993_02
Patent number
US05185442

Reaction notes

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