Synthesis and Characterization of novel Re(BIAN)(CO)3Cl Derivatives including the first Example of a Water-Soluble Tricarbonyl Rhenium(I) Complex with Bis(imino)acenaphthene Ligands

A series of rhenium(I) carbonyl chloride complexes carrying bis(imino)acenaphthene (BIAN) ligands as π-acceptor subunits was prepared and characterized by various spectroscopic techniques. Among the novel compounds described, the remarkable example of a deeply coloured water-soluble rhenium carbonyl derivative is presented. The crystal structures of this family of BIAN-compounds are also reported, which confirm the position of the chloro ligand at the tricarbonyl rhenium(I) center. In the case of BIAN-ligands carrying bulky substituents in the ortho-position of the arylimino subunits, some evidence is found for a potential exchange of the halide ligand in solution, which is considered to be of major relevance for catalytic applications. Implications of our results for the fields of photocatalytic CO2 reduction and the controlled release of the gasotransmitter CO in aqueous solution are briefly discussed.