The introduction of electron‐withdrawing pentafluoroethyl groups into organosilicon, organogermanium and organotin compounds by the treatment of organo‐element halides with LiC2F5 creates a pronounced electron‐deficiency at the central atom with respect to non‐fluorinated derivatives. For silicon, germanium and tin reliable protocols for a cleavage of the organic protecting groups allow the synthesis of the Lewis acidic pentafluoroethyl‐element halides E(C2F5)4−nXn (E=Si, Ge, Sn; n=1–3). For a detailed discussion of this field of research see the Concept article by M. Wiesemann and B. Hoge on page 16457 ff.