(E)-1-Trimethylsilyl-1, 2, 3, 4, 4-pentafluoro-1, 3-butadiene (1) can be stereospecifically prepared by Pd (0)/CuI catalyzed cross-coupling of (Z)-1-tributylstannyl-1, 2-difluoro-2- trimethylsilylethene with iodotrifluoroethene. The corresponding (E)-1-tributylstannyl-1, 2, 3, 4, 4-pentafluoro-1, 3-butadiene can be prepared via the stereospecific conversion of 1 with Bu3SnOSnBu3/KF (catalysis) to the corresponding vinylstannane.