Dimetal‐Binding Scaffold 2‐(Pyridin‐2‐yl)imidazo [1,5‐b]pyridazine‐7‐ylidene: Synthesis of Trinuclear Heterobimetallic Complexes Involving Gold‐Metal Interactions

Abstract

AbstractAs a dimetal‐binding rigid scaffold, 2‐(pyridin‐2‐yl)imidazo[1,5‐b]pyridazine‐7‐ylidene was introduced. The scaffold was first converted into a meridional Au,N,N‐tridentate ligand through binding of a Au(I)Cl moiety at the carbene center. The Au(I) center and the N,N‐chelating moiety were expected to function as metallophilic and 4e‐σ‐donative interaction sites, respectively, in the binding of the second metal center. In this manner, various trinuclear heterobimetallic complexes were synthesized with different 3d‐metal sources, such as cationic CuI, CuII, NiII, and CoII salts. SC‐XRD analysis showed that the mono‐3d‐metal di‐gold(I) trinuclear heterobimetallic complexes were constructed through gold(I)‐metal interactions. Metallophilic interactions were also investigated by quantum chemical calculations including the AIM and IGMH methods.