Allylic sulphones 4 + 3-cycloaddition

Acetoxymethyl)allyl]trimethylsilane (5) in the presence of a Pd(0) reagent, for instance, acts as an equivalent of trimethylenemethane in cycloadditions to electron-deficient alkenes such as a,p-unsaturated ketones, esters, nitriles, sulphones and lactones [7] (Scheme 6.6). 

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