Structure and Reactivity of 1,8-Bis(naphthalenediyl)dipnictanes

Syntheses and solid-state
structures of diarsane Naph2As2 (Naph = 1,8-naphthalenediyl, 1) and (Naph)5Sb4Cl2 3 are reported and
the σ-donor capacity of Naph2E2 (E = As 1, Sb 2) was studied in reactions with (coe)­Cr­(CO)5 (coe = Z-cyclooctene), yielding [Naph2As2]­[Cr­(CO)5]2 (4) and [Naph2E2]­[Cr­(CO)5] (E = As 5, Sb 6). In contrast, reactions of 1 and 3 with Me2SAuCl proceed with oxidation
and formation of elemental gold as well as Naph2(AsCl)2 (7) and [NaphSbCl2]2 8. All complexes were characterized by elemental analyses,
heteronuclear (1H, 13C) NMR and FT-IR spectroscopy,
as well as single crystal X-ray diffraction. Intermolecular E···π
interactions (E = As, Sb), which were observed in 7 and 8, were quantified by use of density functional theory and
local coupled cluster electronic structure theory calculations. These
allow to assess the nature and relative importance of covalent and
noncovalent interactions and illustrate how dispersion interactions
change with the electronic structure of the compounds.