Detalle de: Be‐ and Mg‐Based Electron and Anion Sponges

By using G4(MP2) high‐level ab initio methods, we show that Be and Mg derivatives of cyclopropane exhibit very large electron and anion affinities, reflecting the electron‐deficient nature of the −BeX and −MgX (X=CH 3 , F, Cl, CN) substituents. In particular, these compounds present electron affinities among the largest reported for neutral closed‐shell systems. Their anion affinities are also among the largest reported for single neutral molecules, indeed higher than the 1,8‐diBeX‐naphthalene (X=F, Cl, CN) derivatives, recently shown to behave as anion sponges. Quite unexpectedly, our results indicate that the intrinsic anion affinity of the Mg‐containing compounds is higher than that of the Be‐containing analogs.