Dimethyl Sulfoxide → Stilbene

Participants

Reaction Conditions

Reaction Steps

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.

Provenance & Evidence