AbstractTreatment of 3‐phenylthio‐2‐sulfolene (1) with an equimolar proportion of butyllithium at −78 °C in THF followed by addition of an electrophile gave the 2‐substituted 3‐phenylthio‐2‐sulfolenes (2). The deprotonation was found to proceed only at the vinylic C‐2 position. Some of the 2‐sulfolenes 2 underwent desulfonylation upon heating with base. Of particular interest was the conversion of 3‐phenylthio‐2‐trimethylsilyl‐2‐sulfolene (2h) to its 3‐sulfolene isomer6by sequential addition of butyllithium and salicylic acid at low temperatures. The 3‐sulfolene6was desulfonylated by Kugelrohr distillation at 150° C under vacuum to give (Z)‐2‐phenylthio‐l‐trimethylsilyl‐1,3‐butadiene (8). The regiochemistry of the Diels Alder reaction of this highly reactive diene8was found to be controlled by the phenylthio group, and the stereochemistry isendoaddition. Diene8was oxidized to its sulfone derivative12which also