6‑Diphenylphosphinoacenaphth-5-yl-mercurials as Ligands for d10 Metals. Observation of Closed-Shell Interactions of the Type Hg(II)···M; M = Hg(II), Ag(I), Au(I)

The salt metathesis reaction of ArLi with HgCl2 produced Ar2Hg (1, Ar = 6-Ph2P-Ace-5), which underwent complex formation with d10-configurated transition metal chlorides and triflates to give the complexes 1·HgCl2, 1·Hg­(O3SCF3)2, 1·AgCl, 1·Ag­(O3SCF3), [1·Ag­(NCMe)2]­(O3SCF3), 1·AuCl, and [1·Au]­(O3SCF3) comprising significant metallophilic interactions between Hg­(II) and Hg­(II), Ag­(I), and Au­(I), respectively. The transmetalation reaction of ArSnBu3 with HgCl2 afforded ArHgCl (2) that also forms a complex with additional HgCl2, namely, 2·HgCl2, which however lacks metallophilic interactions. Compounds 2 and 1·HgCl2 possess the same elemental composition and can be interconverted in solution by choice of the solvent. In the presence of tetrahydrothiophene (tht), the complexes 1·AuCl and [1·Au]­(O3SCF3) underwent rearrangement into the Au­(III) cation [cis-Ar2Au]+ ([3]+, which was isolated as Cl and (O3SCF3) salts) and elemental Hg. The reaction of 1·Hg­(O3SCF3)2 with ArH produced the complex ArHg­(ArH)­(O3SCF3) (4). The metallophilic interactions are theoretically analyzed by a set of real-space bonding indicators derived from the atoms-in-molecules (AIM) and electron localizability indicator (ELI) space-partitioning schemes.