2-silylbut-2-ene-1,4-diol derivatives 2 bearing different substituents on the silicon atom have been prepared and tested in palladium-catalyzed alkylations with dimethyl malonate. Totally chemo- and stereoselective, these high yielding reactions are strongly influenced by the presence of the silicon group on the allyl moiety. The preparation and reactivity of two analogues 9 where the silyl group is replaced