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A novel approach is described for the construction of multicomponent two-dimensional (2-D) and three-dimensional (3-D) metallosupramolecules. This method is used for preparing a variety of 2-D rectangles and 3-D prisms and multicomponent self-assembly is achieved by supramolecule-to-supramolecule transformations.

The key intermediate in dinitrogen cleavage by Mo[(N[t-Bu]Ar).sub.3] (Ar = 3,5-[C.sub.6][H.sub.3][Me.sub.2]) are characterized by a pair of single crystal x-ray structures. The primary quantum yield is determined and the transient absorption experiments have shown that the photochemical reaction is complete in less than 10 ns.

The first [Pt.super.III]-[Au.super.II] complex were prepared and structurally characterized. They show that this complex exhibits a facile two-electron chemically assisted halogen photoelimination that is prompted by visible light.

We present the formation of a series of chiral metallacycles and metallacages by the use of a BINOL-derived dicarboxylate as a donor that is capable of affording a variety of coordination angles between its two Lewis basic sites. Two squares, two rhomboids, two tetragonal prisms, and one hexagonal prism were successfully formed when the chiral dicarboxylate donor self-assembled with one of four ditopic Pt(II) complexes, including two bimetallic 180° Pt-based acceptors, a 120° bimetallic Pt-based acceptor, and a 90° mononuclear Pt-based acceptor. Their structures were well characterized by 31P{1H} NMR, ESI-MS, CD, and optical rotation analyses. [ABSTRACT FROM AUTHOR]

Oligo(ethylene glycol) (OEG)-decorated supramolecular assemblies are distinguished by their neutral character and macroscopic temperature-sensitive phase transition behavior. OEG functionalization is an emerging strategy to obtain thermoresponsive macrocyclic amphiphiles, although known methods organize the hydrophilic and hydrophobic segments by covalent bonding. Coordination-driven self-assembly offers an alternative route for organizing OEG-functionalized precursors into nanoscopic architectures, resulting in well-defined metallacycle cores surrounded by hydrophilic scaffolds to impart overall amphiphilic character. Here a tri(ethylene glycol)-functionalized thermosensitive amphiphilic metallacycle was prepared with high efficiency by means of the directional-bonding approach. The ensembles thus formed showed good lower critical solution temperature behavior with a highly sensitive phase separation and excellent reversibility. Moreover, the clouding point decreased with increasing metallacycle concentration and addition of K+. [ABSTRACT FROM AUTHOR]

An emerging strategy for the fabrication of advanced supramolecular materials is the use of hierarchical self-assembly techniques wherein multiple orthogonal interactions between molecular precursors can produce new species with attractive properties. Herein, we unify the spontaneous formation of metal-ligand bonds with the host/guest chemistry of crown ethers to deliver a 3D supramolecular polymer network (SPN). Specifically, we have prepared a highly directional dipyridyl donor decorated with a benzo-21-crown-7 moiety that undergoes coordination-driven self-assembly with a complementary organoplatinum acceptor to furnish hexagonal metallacycles. These hexagons subsequently polymerize into a supramolecular network upon the addition of a bisammonium salt due to the formation of [2]pseudorotaxane linkages between the crown ether and ammonium moieties. At high concentrations, the resulting 3D SPN becomes a gel comprising many cross-linked metallohexagons. Notably, thermo- and cation-induced gel-sol transitions are found to be completely reversible, reflecting the dynamic and tunable nature of such supramolecular materials. As such, these results demonstrate the structural complexity that can be obtained when carefully controlling multiple interactions in a hierarchical fashion, in this case coordination and host/guest chemistry, and the interesting dynamic properties associated with the materials thus obtained. [ABSTRACT FROM AUTHOR]

The article offers information on a research conducted in order to determine chlorine photoelimination. The research has revealed that photolysis of a Pt2 with ultraviolet (UV) or visible light in the solid state yields chlorine. The research has also revealed energy storage reactivity in the absence of a halogen trap.

The article describes the preparation and characterization of the first PtAu compound. According to the authors, the d7-d9 complex exhibits a facile two-electron chemically assisted halogen photoelimination that is promoted by visible light. They add the electronic absorption spectrum of platinum compound features a dominant band centered at 338 nm.