Reverse Arene Sandwich Structures Based upon π-Hole⋅⋅⋅[M ] (d M=Pt, Pd) Interactions, where Positively Charged Metal Centers Play the Role of a Nucleophile.

The complexes [Pt(tpp)] (H tpp=tetraphenylporphyrin), [M(acac) ] (M=Pd, Pt, Hacac=acetylacetone), and [Pd(ba) ] (Hba=benzoylacetone) were co-crystallized with highly electron-deficient arene systems to form reverse arene sandwich structures built by π-hole⋅⋅⋅[M ] (d M=Pt, Pd) interactions. The adduct [Pt(tpp)]⋅2 C F is monomeric, whereas the diketonate 1:1 adducts form columnar infinity 1D-stack assembled by simultaneous action of both π-hole⋅⋅⋅[M ] and C⋅⋅⋅F interactions. The reverse sandwiches are based on noncovalent interactions and calculated ESP distributions indicate that in π-hole⋅⋅⋅[M ] contacts, [M ] plays the role of a nucleophile.