γ-Allyl Phosphinoyl Phenyl Sulfone (GAPPS):  A Conjunctive Reagent for the Synthesis of EE, EZ, and ET 1,3-Dienes^†

A three-operation conjunctive strategy is available for the synthesis of EE, EZ, and ET dienes. This protocol employs a sequential Wadsworth−Emmons reaction using a GAPPS reagent followed by alkylation of an allylic sulfone anion, and finally ligand-mediated, palladium-catalyzed desulfonylation.