Isocyanide π-Hole Interactions Supported by Aurophilic Forces

Treatment of the [AuCl(tetrahydrothiophene)] complex with 4-chloro-2-iodo-1-isocyanobenzene furnished the gold(I) compound [AuCl(CNC6H3-4-Cl-2-I)] (1). In the crystal structure of 1, the linear C–Au–Cl group is subject to the solid-state head-to-tail pairing, which is determined by the aurophilic Au⋯Au and the rare π-holeCN⋯Cl interactions. These two types of structure-determining interactions are complementary to each other, and the system of Au⋯Au and CCN⋯Cl contacts accomplishes a 2D extended ladder-type architecture. In addition, the terminal I-atoms are involved in the three-center halogen bonding. Density functional theory calculations, employing a set of computational tools, verified the role of Au⋯Au and π-holeCN⋯Cl noncovalent bonds in the spectrum of noncovalent forces.