Bifunctionalized Allenes. Part VIII. An Efficient and Varied Method for the Synthesis of 2-Sulfonylated Alka-2,3-Dienoates

An efficient and varied method for the synthesis of 2-sulfonylated alka-2,3-dienoates by intermediate formation of allenecarboxylates, allenyl sulfones, and propargyl sulfinates using the relatively high acidity of the hydrogen atom at the allenic C-1 atom and the [2,3]-sigmatropic rearrangement is described.