Design, synthesis and characterization of self-assembled As2L3 and Sb2L3 cryptands.

The syntheses and X-ray crystal structures of six new self-assembled supramolecular As and Sb-containing cryptands are described. Analysis in the context of previously reported As(2)L(3) and Sb(2)L(3) cryptands reveals that small differences in ligand geometries result in significant differences in the helicity of the complexes and the stereochemistry of the metal coordination within the assembled complexes. Additionally, a new synthetic route is described which involves exposure of reactants to vacuum to help facilitate self-assembly.

Multiple weak supramolecular interactions stabilize a surprisingly twisted As2L3 assembly.

A combined crystallographic, DFT and NMR spectroscopic study of a flexible As(2)(3) assembly reveals temperature dependent conformational behavior in solution and a highly asymmetric structure stabilized by As-pi and edge-to-face aromatic interactions.

Host-guest interactions in a series of self-assembled As2L2Cl2 macrocycles.

The reaction of AsCl3 with H2L (where L = a rigid dithiolate) results in the self-assembly of As2L2Cl2 supramolecular macrocycles. For ligands 4,4'-bis(mercaptomethyl)biphenyl (H2), 4,4'-bis(mercaptomethyl)-trans-stilbene (H2), and 1,4-dimethoxy-2,5-bis(mercaptomethyl)benzene (H2), the macrocyclic cavities of the resulting assemblies are large enough to host aromatic solvent molecules, as revealed by single crystal X-ray structures of the inclusion complexes. As2L2Cl(2) macrocycles form in solution as a mixture of diastereomers, but the diastereomers can be selectively crystallized and separated. Crystallization of syn- or anti-As(2)3(2)Cl2 can be controlled using host-guest interactions by the prudent choice of crystallization solvents. anti-As(2)3(2)Cl2 crystallizes exclusively from chloroform and benzene, while a [(syn-As(2)(2)Cl(2))(2).p-xylene] dimer crystallizes from p-xylene and a mixture of [(syn-As(2)3(2)Cl(2))(anti-As(2)3(2)Cl2) x toluene] and [(syn-As(2)3(2)Cl2)2 x toluene] dimers crystallize from toluene.

Main group supramolecular chemistry.

Metal directed self-assembly has yielded a wide array of two- and three-dimensional structures with fascinating new chemical properties. These structures have typically been prepared utilizing transition metals as directing units, owing to the well-defined coordination preferences these metals exhibit. An area of growing research interest involves the preparation of structures containing main group elements as directing units. This tutorial review surveys the wide range of structure types available through this approach, specifically covering unique structure types accessible from the unusual coordination geometries often exhibited by the elements in Groups 12-17 of the periodic table. This review should be of interest to supramolecular and main group chemists, and researchers in the fields of crystal engineering, host-guest chemistry, and molecular recognition.

Secondary bonding interactions observed in two arsenic thiolate complexes.

Treatment of N-(2-mercaptoethyl)-1,8-naphthalimide (HL) with stoichiometric amounts of AsCl(3) and base affords AsL(2)Cl and AsL(3) complexes stabilized in part by secondary As...O bonding interactions.