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Two structurally simple and easily synthesized luminescent anion receptors featured with an amide-type anion binding site and rhenium(I) tricarbonyl pyridine signaling units have been developed, and they display outstanding sensitivity and selectivity toward a variety of anionic species. These complexes are highly emissive in solution. Upon anion binding, the emission intensity was significantly quenched. The sensitivities of these complexes are so high that the emission intensity can be effectively quenched by as much as 10% even in the presence of only 10(-8) M cyanide or fluoride anions. The ability of formation of intramolecular hydrogen bonding between the amide protons and central pyridine is believed to be responsible for the observed high selectivity.

This review describes our recent research results on several transition-metal based supramolecular systems. A number of self-assembly metallocyclophanes and cages have been prepared. We have found that the photophysical properties of these systems are highly dependent on the nature of the bridging ligands and that many of these metallocyclophanes and cages are capable of binding different guest molecules such as inorganic anions and a variety of aromatic compounds. Moreover, trinuclear (diimine) rhenium(I) tricarbonyl complexes linked by a stilbene-like ligand exhibit most interesting photoswitching features, where the luminescence from the complexes can be switched on and off by photoinduced ligand isomerization. In addition, a structurally simple and easily synthesized luminescent anion receptor has been recently developed and it displays outstanding sensitivity and selectivity toward anionic species. We also review the synthesis of two shape-persistent hexagonal phenylacetylenes and their use as ligands to synthesize dinuclear transition-metal complexes. The photophysical properties of both phenylacetylenic ligands and their corresponding metal complexes are summarized. [Copyright &y& Elsevier]

Investigates a series of heterometallic square complexes prepared by self-assembly. Molecular structures of the complexes with terpyridyl metal complexes as bridging ligands; Multiple redox processes; Metal-to-ligand charge transfer; Band structure; Luminescence; Electrochemical and photophysical properties.

Studies the thermal chemistry and photochemistry of the intermolecular C-H bond activating a rhenium organometallic complex in various alkane solutions at 293 K. Nature of electronically excited states; Photochemical C-H bond activation; Photochemical Si-H bond activation; Photophysical interpretation.

The quantitative photochemistry of the platinum organometallic complex, Cp'Pt(CH3)3 (Cp' = η5-C5H4CH3), has been investigated in methylcyclohexane and n-pentane solutions at 293 K following UV irradiation into the lowest lying absorption bands. Absolute photochemical quantum efficiency (φcr) results obtained for Cp'Pt(CH3)3 at 313 and 366 nm reveal that the system very effectively photoreacts with φcr = 0.34-0.41 in these solvents and 0.79-0.85 when 53 mM Et3SiH is incorporated. These photoefficiencies indicate that the quantitative photochemistry is 2 orders of magnitude higher than previously recognized. The application of Cp'Pt(CH3)3 as an effective photoinitiator for hydrosilylation reactions involving vinyl/hydride silicone mixtures is demonstrated. [ABSTRACT FROM AUTHOR]