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A series of dimeric ReI(CO)3 compounds have been prepared by means of a one-pot reaction of [Re(CO)5X] (X = Cl, Br), pyridine-2-carboxyaldehyde, and o-, m-, or p-phenylenediamine. For the m- and p-substituted phenylenediamine reactions, phenyl-bridged bis(pyridine-2-carbaldimine) compounds of the formula [Re(CO)3X]2(μ-PPC) [ 3- 7; X = Cl, Br; μ-PPC = m- or p-phenylene bis(pyridine-2-carbaldimine)] were produced, with m-phenylenediamine forming a mixture of isomers. For reactions with o-phenylenediamine, multiple products formed (compounds 8- 11), which ranged from the desired o-phenylene bis(pyridine-2-carbaldimine) adduct to 2-pyridylbenzimidazole and bridging dipyridinylquinoxaline complexes. An example of each complex was structurally elucidated by single-crystal X-ray methods. The dimeric m- and p-phenylene-bridged Re(CO)3X compounds, including a sulfonate derivative designed to improve solubility, were investigated for possible photophysical applications through the use of UV/Vis spectroscopy and cyclic voltammetry; the study revealed coupling between the rhenium centers. [ABSTRACT FROM AUTHOR]

The reaction of [Re(CO)3(H2O)3]Br or [Re(CO)5Cl] with two peptides, glycylglycine, or glycylalanine were investigated. Each reaction produced a unique, well-defined product. Structural elucidation showed the formation of chiral compounds with the formula [Re(CO)3(Gly-Xxx-O)]2, Xxx = Gly ( 1), Ala ( 2). Each dimer displays C2 symmetry and a nearly rectangular shape. The ligands are bound through the amine and amide carbonyl at a rhenium center and through the pendant carboxylate to the adjacent rhenium center. Both products are fully characterized by X-ray structure elucidation. [ABSTRACT FROM AUTHOR]