3,5-Bis(trifluoromethyl)phenyl sulfones in the modified Julia olefination: application to the synthesis of resveratrol

The reaction between carbanions derived from alkyl 3,5-bis(trifluoromethyl)phenyl sulfones and aldehydes, affords with good yields and stereoselectivities the corresponding 1,2-disubstituted alkenes through the Julia–Kocienski olefination reaction. This one-pot protocol can be performed using KOH at room temperature or the phosphazene base P4-t-Bu at −78 °C, and has been successfully used in a high yielding and stereoselective synthesis of various stilbenes such as resveratrol.