The interplay of metal and supporting ligand in labile coordination to pincer complexes of Ag(i)

Abstract

The bis(imino)pyridine scaffold provides support for the synthesis and characterization of unique Ag(I) pincer complexes [{ArNCPh}₂(NPh)]Ag⁺(OTf)⁻ (Ar = 2,5-^tBu₂C₆H₃3; 2,6-ⁱPr₂C₆H₃4). The bonding interactions between the cation–anion and between the bis(imino)pyridine ligand and the Ag centre are presented. Coordination of pyridine, toluene, 2-butyne and cyclooctene to the Ag centre led to the isolation and crystallographic characterization of labile transient adduct species. Bonding analysis of the adducts revealed conventional ligand–Ag coordination and important unconventional electron donation from the ligand to a π*-orbital of the bis(imino)pyridine group.