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A class in a Scientific-Technological Lyceum (age 17) decided to produce a PowerPoint presentation to introduce nanochemistry and nanotechnology to the students in lower grades. Because the subject is very new, there was nothing in the School textbooks and, therefore, the students had to cooperate in order to find materials, to use ICT sources and to take decisions, such as selecting information and choosing slide layouts. Furthermore, the Cooperative Learning methodology was employed to solve the problem of setting up the presentation. To make nanochemistry and nanotechnology a reality for the students, they used a link between these new frontiers of Chemistry and subjects currently tackled at the Secondary School level. This was the quantitative determination of Ca[superscript 2+] ions by using calcein, a luminescent chemosensor, in which well known concepts, such as chemical equilibrium and stability constants of coordination compounds, are involved. The educational aims of the project were to promote both content knowledge and social skills in Secondary School students. The activity created a good class atmosphere and also led to the retention of content knowledge. (Contains 4 tables and 1 figure.)

A calix[6]arene wheel, whose cavity is extended and rigidified by N-phenylureido groups on the upper rim, forms pseudorotaxane species with molecular axles containing the viologen (4,4'-bipyridinium) unit in CH2Cl2 solution. The ion-pair recognition and the rate constants of the threading/dethreading reactions coupled with the redox processes of the viologen unit of the axle are obtained by cyclic voltammetry.

Two dendrimers based on a 1, 3, 5-trisubstituted benzenoid-type core, containing 9 and 21 viologen units in their branches and terminated with tetraarylmethane derivatives is presented. The host-guest interaction can be destroyed by addition of chloride ions, a procedure that permits eosin to escape from the dendrimer's interior in a controlled way and to regain its intense fluorescence.

Research has been conducted on the trinuclear pyrazine-bridged ruthenium complexes. The study of the complexes' electrochemistry carried out in examining the stability of the trinuclear species in various oxidation states is presented.

The synthesis of four ferrocene-containing acyclic polyethers and the absorption properties of the adducts are demonstrated. Results describe the reversible decomplexation/recomplexation of one of the adducts upon oxidation/reduction of the ferrocene unit in the guest and reduction/oxidation of the bipyridinium units in the host.

Research describes the synthesis of an acyclic polyether containing an electron donor tetrathiafulvalene and two 4-tert-butylphenoxy groups along with two other polyethers, incorporating two different electron donoros. Data discuss chemical and electrochemical switching between the pseudorotaxane and catenane species of the tetrathiafulvalene unit.

Six new dendrimers constructed around a (Ru(bpy)3)2+-type core (bpy = 2,2'-bipyridine) and having up to 24 4'-tert-butylphenyloxy or 48 benzyl units in the periphery were synthesized. The metallodendrimers were produced by complexation of ruthenium trichloride with bipyridine ligands with dendritic wedges in the 4,4'-positions. All of them exhibited the characteristic luminescence of the (Ru(bpy)3)2+-type core unit. The dendritic branches protect the luminescent excited state of the core by dioxygen quenching.

Tetrathiafulvalenium dication (TTF(super 2+)) binds strongly within the cavity of the pi-electron-donating macrocyclic polyether 1,5-dinaphtho(38)crown-10, producing a host-guest complex that is stabilized by pi-pi stacking interactions. This makes it possible to use the properties of TTF to construct a three-pole supramolecular switch whereim electrochemical stimuli can be utilized to shift the system between three states. Data from electrochemical experiments reveal that the three-component mixture behaves as a reversible three-pole supramolecular switch.

A study is conducted on the complexes ((DEAS-bpy)Re(BPP))+, ((DEAS-bpy)Re(BPP-Me))2+ and ((DEAS-bpy)2Re2(mu-BPP))2+. It is shown that the DEAS-bpy ligand is an electron donor while the BPP ligand is an electron acceptor. The simultaneous coordination of BPP and DEAS-bpy on the same metal center also results in donor-acceptor complexes that form long-lived charge-separated state following light excitation.

Catenanes are becoming commonly used molecular compounds. The preparation of [3]catenates with copper as a template has resulted in the successful production of catenates containing between two and seven interlocked rings. Further, certain polycatenanes have been formed by polymerization of preformed bifunctional [2]-catenane monomers. Research on catenanes and their formation are analyzed and discussed.