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The spectroscopic and electrochemical behavior of the symmetric and unsymmetric first-, second-, and third-generation dendrimers (Dn)(sub 2)B(super 2+) (symmetric dendrimers) and DnB(super 2+) (unsymmetric dendrimers) (n = 1,2,3) and their host-guest complexes with tweezer T is investigated. The host-guest complexes between the tweezer and the dendrimers are stabilized by electron donor-acceptor interactions and can be reversibly assembled or disassembled by electrochemical stimulation.

The complexation of the luminescent lanthanide ions by a polylysin dendrimer that contains 21 amide groups in the interior and 24 dansyl units in the periphery are analysed. Result revealed that the formation of the metal complexes is accompanied by a quenching of the fluorescent excited state of the dansyl units and sensitized near-infrared emission of the lanthanide ion in fluid solution at 298 K.

Co2+ ion interaction with dendrimers of the poly(propylene amine) group with densyl units, is discussed.

The preparation and properties of poly(propylene amine) dendrimers are reported.

The electrochemical properties of a family of pyrrolidinium salt analogues of C60 were investigated. A series of N-methylpyrrolidinium fullerene iodide salts consisting of one or two solubilizing chains was synthesized for this purpose. Experimental results showed that the pyrrolidinium salt derivatives exhibit increased electron-accepting properties with respect to C60 and the parent fulleropyrrolidines. Six fullerene-centered reductions were also observed for the first time in the fullerene analogues.

A study was conducted on the electrochemistry at very positive potentials in liquid SO2 of RuII and OsII dendritic polynuclear complexes and of several of their lower-nuclearity analogues. The experiments resulted in the observation of several metal- and ligand-centered oxidations which were previously inaccessible. The findings also suggest that the redox properties can also be employed as a powerful tool for the chemical characterization of large and highly charged supermolecules.

The adducts formed by eosin with a fourth generation dendrimer that comprises 30 tertiary amine units in the interior and 32 naphthyl and 32 trans azobenzene units in the periphery. The results have shown that the isomerization of the 32 peripheral azobenzene units controls to some extent the hosting capacity of the dendrimer and eosin molecules hosted in the dendrimer affect the isomerization process of its azobenzene units.

An investigation is carried out on the assembly/disassembly of the luminescent dendritic hosts with the luminescent metal complex [Ru(bpy)(CN)4](super 2-). It is shown that upon simulation with two chemical inputs [Ru(bpy)(CN)4](super 2-).(2H+).1 and [Ru(bpy)(CN)4](super 2-).(2H+).2 exhibit two distinct optical outputs that behave according to an XOR and an XNOR logic, respectively.

1,4,8,11-Tetraazacyclotetradecane (cyclam), which is one of the most extensively investigated ligands in coordination chemistry, in its protonated forms, can play the role of host toward cyanide metal complexes. We have investigated the acid-driven adducts formed in acetonitrile-dichtoromethane (1:1 v/v) solution by [Ru(bpy)(CN)4]2- with 1,4,8,1 1-tetrakis(naphthylmethyl)cyclam (1) and a dendrimer consisting of a cyclam core appended with 12 dimethoxybenzene and 16 naphthyl units (2). (Ru(bpy)(CN)4]2-, 1, and 2 exhibit characteristic absorption and emission bands, in distinct spectral regions, that are strongly affected by addition of acid. When a solution containing equimolar amounts of [Ru(bpy)(CN)4]2- and 1 or 2 is titrated by trifluoroacetic acid, or when [Ru(bpy)(CN)4]2- is titrated with (1.2H)2+ or (2.2H)2+, {[Ru(bpy)(CN)4]2-·(2H+)·1 } or {[Ru(bpy)(CN)4]2-·(2H+)·2} adducts are formed in which the fluorescence of the naphthyl units is strongly quenched by very efficient energy transfer to the metal complex, as shown by the sensitized luminescence of the latter. The {[Ru(bpy)(CN)4]2-·(2H+)·1} and {[Ru(bpy)(CN4]2-·(2H+)·2} adducts can be disrupted (i) by addition of a base (1,4-diazabicyclo[2.2.2]octane), yielding the starting species [Ru(bpy)(CN)4]2- and 1 or 2, or (ii) by further addition of triflic acid, with formation of (1.2H)2+ or (2.2H)2+ and protonated forms of [Ru(bpy)(CN)4]2-. It is shown that upon stimulation with two chemical inputs (acid and base) both {[Ru(bpy)(CN)4]2-·(2H+)·1} and {[Ru(bpy)(CN)4]2-·(2H+)·1} exhibit two distinct optical outputs (a naphthalene-based and a Ru(bpy)-based emission) that behave according to an XOR and an XNOR logic, respectively. [ABSTRACT FROM AUTHOR]