Metallosupramolecular self-assembly strategies and principles have been thoroughly investigated in the past 20 years with the aim of mimicking natures ability to assemble impressive supramolecular structures.[1] Despite the remarkable metal selectivity and recognition in self-assembly reactions, directed metal exchange (i.e. transmetalation) in such supramolecular structures is still underdeveloped, [2] which is surprising as transmetalation is the missing link between the currently known self-assembly strategies "classical selfassembly" and "subcomponent self-assembly". Classical self-assembly of pre-designed ligands with suitable metal ions is a powerful tool, and is most impressively demonstrated by the synthesis of molecular clusters and their application as hosts, [3] catalysts, [4] and molecular traps. [5] However, this strategy is limited by the often time-consuming synthesis of pre-designed ligands and their intrinsic stability.[6] Developing an alternative approach, Nitschke et al. recently described the "subcomponent self-assembly" strategy, which is based on the reversible condensation of suitable amines at metal-coordinated aldehydes under formation of the thermodynamically most stable product. [7] Although this strategy has led to impressive results, such as the assembly of an unlockablerelockable molecular cage, [8] it is still limited by the need for stable (subcomponent) precursor complexes that allow reversible imine formation within their metal coordination sphere. [8,9] Transmetalation of supramolecular structures obtained by classical or subcomponent assembly constitutes a promising strategy to overcome these shortcomings. Following this strategy, supramolecular structures containing ligands not accessible by conventional organic synthesis could be obtained by subcomponent assembly, and transmetalation will subsequently allow the use such ligands in classical supramolecular chemistry. Herein, we present the subcomponent self-assembly of dinuclear complexes and the subsequent transmetalation reaction.Building on our previous work involving sulfur-containing ligands, [10] we investigated the incorporation of the sulfur donor function into Schiff base ligands. In contrast to most Schiff bases, the thiosalicylaldimine (o-mercaptobenzaldimine) subunit is not accessible by direct condensation of an amine with the corresponding o-mercaptobenzaldehyde, which instead leads to 1,5-dithiocines.[11] However, treatment of a preformed complex bearing 2-thiolatobenzaldehyde ligands with appropriate primary amines leads in a template-controlled reaction to the desired complexes with N,S donor functions. [12] We found that nickel(II) and zinc(II) are excellent templates for this chemistry, as indicated by the facile synthesis and stability of the 2-thiolatobenzaldehyde complexes 1 and 2 (Scheme 1). While the molecular structure of the square-planar nickel complex 1·CHCl 3 (see the Supporting Information) shows the cis configuration of the oxygen donors, zinc complex 2 probably has a tetrahedral coordinati...

The dicarbene silver complexes 1a, b of the type [Ag(NHC)2][AgBr2] (NHC = N,N'-dialkylbenzimidazolin- 2-ylidene) have been prepared from the parent benzimidazolium salts by reaction with silver oxide. The silver complexes have been used for the transfer of the carbene ligand to gold(I) giving the gold complexes [AuCl(NHC)] 2a, b in good yields. Crystals of 2a, b have been obtained from chloroform/pentane solutions, and X-ray diffraction structure analyses revealed gold(I) atoms coordinated in a linear fashion by an NHC carbon atom and a chloro ligand

The cyclic tetraamine 2, prepared by the hydrogenation of tetraimine 1, was used for the preparation of the macrocyclic bisgermylene 3 with two lutidine bridging groups. The molecular structure determination of tetraamine 2 exhibits a C i -symmetric

Swing bridge: The triplet species ethenedithione has been generated within the coordination sphere of cobalt, leading to a dinuclear μ-η(2)-η(2)-C(2)S(2) complex (see picture: C gray, Co blue, P purple, S yellow). Depending on the solvent, the C(2)S(2) moiety displays a transoid or a cisoid geometry. This isomerization step changes the sign of the magnetic coupling between the cobalt centers.

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