Homo‐ and Heteroligand Poly‐NHC Metal Assemblies: Synthesis by Narcissistic and Social Self‐Sorting.

Homoleptic and heteroleptic cylinder‐shaped poly‐NHC metallosupramolecular assemblies [Ag3(L)2](BF4)3 have been prepared by control of the shape, size, and electronic properties of disk‐shaped trisimidazolium salts of type H3‐L(BF4)3. Both imidazolium salts with an electron‐deficient triazine backbone H3‐A(BF4)3 or an electron‐rich benzene backbone H3‐D(BF4)3 have been employed. Reaction of H3‐A(BF4)3 or H3‐D(BF4)3 with Ag2O yield trinuclear homoligand complexes [Ag3(L)2](BF4)3 (L=A, D). However, equimolar mixtures of H3‐A(BF4)3 and H3‐D(BF4)3 react with Ag2O under social self‐sorting to give the heteroligand assembly [Ag3(A)(D)](BF4)3. The same heteroligand assembly was obtained by transmetallation from mixtures of complexes [Ag3(A)2](BF4)3 and [Ag3(D)2](BF4)3. The transmetallation from [Ag3(A)(D)](BF4)3 to [Au3(A)(D)](BF4)3 is also demonstrated. The study expands to concepts of narcissistic and social self‐sorting from classical Werner‐type ligands to organometallic NHC chemistry thereby opening new routes for the construction of poly‐NHC metal assemblies with increasing complexity. Unprecedented social self‐sorting occurs during the reaction of Ag2O with two trisimidazolium salts featuring either an electron‐poor H3‐A1(BF4)3 or an electron‐rich H3‐D1(BF4)3 backbone to give the heteroligand assembly [Ag3(A1)(D1)](BF4)3 most likely driven by π⋅⋅⋅π stacking interactions between the electron‐rich and electron‐poor ligand backbone groups. [ABSTRACT FROM AUTHOR]