AbstractA new stereospecific synthesis for substituted 1‐alkenyl sulfides, phosphines and tin compounds RR′C=CHX (X = −SMe, −PPh2, −SnPh3) is presented, starting from stereospecifically generated vinylcuprates [RR′C=CHCu(Br, I or R)]MgX′ (X′ = Cl or Br) and MeSSO2Me, Cl−PPh2and Cl−SnPPh3, respectively, using tetrahydrofuran as solvent.Iodovinylcuprates [RR′CCHCu−I]MgX′ are obtained by selective methylation of the R‐radical in the mixed homocuprates [RR′CCHCu−R]MgX