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Mononuclear ruthenium vinyl complexes L-{Ru}-CH[double bond]CH-R is described where the phosphine ligands, the coordination number at the metal and substituent are varied. The vinyl ligands have contributed to the anodic oxidation processes, rendering them a class of truly 'non-innocent' ligands in organometallic ruthenium chemistry.

The formation of supramolecular networks of [[(Cp*Mo).sub.2][As.sub.2][S.sub.3]] (Cp*=[C.sub.5][Me.sub.5]) from a mixed As/S-ligand complex and copper halides are described. The assembly of the building blocks is promoted by the lone pairs of the central monosulfide bridge of the organometallic complex in all the products and the nature of the products depends on the copper halide used.

Raman experiments have proved that atleast eight vibrational modes are coupled to the optical charge resonance band. The contribution of the symmetric vibrational modes to the reorganization energy is in line with the Marcus-Hush analysis.

Research has been conducted on the acetal produced cyclic enediyne. The structure and synthesis of this compound have been investigated and the details are included.

The structures resulting from the incorporation of the cyclic [C.sup.[alpha]]-tetrasubstituted [alpha]-amino acids into peptides are examined. The studies have shown that the all-S-backbone-configured peptides have formed right-handed [3.sub.10]-helices, while the all-R-configured peptides have formed left-handed [3.sub.10]-helices in the solid state and solution.

Ruthenium and osmium complexes featuring the N-4,6-dioxo-5,5-dibutyl- or the N-4,6-dioxo-5,5-di-(2-propenyl)-1,4,5,6-tetrahydropyrimidin-2-yl-N'(4-ethenylphenyl)-urea ligand are dimerized by a self-complementary quadruply hydrogen-bonding donor/donor/acceptor/acceptor (DDAA) motif. The results have shown that the ureapyrimidinedione (Upy) DDAA hydrogen-bonding motif has not supported the electron transfer, as neither of the hydrogen-bonding functionalities has contributed to the occupied frontier levels.

The synthesis and structural characterization of tetrahydrofuran C[alpha]-tetrasubstituted amino acids from methionine is described. The reaction induces two consecutive [beta]-turns as part of a tripeptide of aliphatic [alpha]-amino acids.

The reaction of [Cp2*Rh2Cl4] (Cp*=C5Me5) with a slight excess of K3SbS3 in boiling THF gave the neutral clusters [Cp*4Rh4S5], [Cp*3Rh3Rb2S5], and after salt metathesis [Cp*3Rh3SbSn]PF6 (3; n=5 and 6). The reaction provides the evidence for the existence of a stable Sb=S double bind being integrated in the novel [SbS4](super 4-) ligand in the trirhodium cluster [Cp*3Rh3Rb2S5].

New metal complexes with pentagonal-bipyramidal geometry are synthesized with the chiral, pententate bis(oxazoline) ligand (R,R), including the metal ions magnesium (II), iron (II), and cadmium(II). All compounds exhibit a very characteristic and almost identical CD pattern between 200 nm and 300 nm.

The synthesis of cyclic 10-membered tetrahydoxy enediynes is described. By the use of additional hydroxy groups, the cyclic enediynes become water soluble and can be regulated in their activity by cyclic protecting groups.

Research has been conducted on functionalized bi- and terpyridines. The authors report the development of the general route for the synthesis of these compounds, and demonstrate that each step of the route allows diversification.

The chiral, C2-symmetric pentadenate bis(oxazoline)ligands for the stereoselective transfer of carbon-centered, tetrahedral chirality to metal centers with various coordination geometries which creates metal complexes with predetermined helicity. It was revealed that the new multidenate ligand is capable of inducing helical topology in inorganic-organic hybrid polyers with unprecedented design and complete steroselectivity.

The synthesis of tetrahydrofuran Cα-tetrasubstituted amino acids (TAAs) and their effect on the conformation in small peptides are reported. The synthesis starts from the protein amino acid methionine, which is protected at the C and N terminus and converted into the corresponding sulfonium salt by alkylation. Simple base treatment in the presence of an aryl aldehyde leads to the formation of tetrahydrofuran tetrasubstituted Cα-amino acids in a highly diastereoselective (trans/cis ratio up to 97:3) reaction with moderate to good yields (35–78%) depending on the aldehyde used. Palladium-catalyzed coupling reactions allow a subsequent further functionalization of the TAA. The R,S,S-TAA-Ala dipeptide amide adopts a β-turn type I conformation, whereas its S,R,S isomer does not. The R,S,S-Gly-TAA-Ala tripeptide amide shows in the solid state and in solution a conformation of two consecutive β-turn type III structures, stabilized by i + 3 → i intramolecular hydrogen bonds. [ABSTRACT FROM AUTHOR]