Oxa-Michael reaction of metallocarbonyl complexes bearing the maleimidato ligand. Reactivity studies with selected hydroxy compounds

Metallocarbonyl complexes display specific and intense absorption bands in the mid-IR spectral range due to the stretching vibrations of carbonyl ligands, which makes them useful labels for biocompounds. In the course of searching for new labelling methods for biomolecules, we attempted O-alkylation of various hydroxyl compounds. Methanol, selected glycols and carbohydrates as well as model nucleoside were subjected to a reaction with metallocarbonyl complexes bearing the maleimidato ligand. In all cases, and using spectroscopic methods, we confirmed the formation of products with the addition of the hydroxyl group to the ethylenic bond of the maleimidato ligand. The ruthenium complex obtained in the reaction with methanol was also characterized by X-ray diffraction.

Graphical abstractOxa-Michael reaction of metallocarbonyl complexes bearing maleimide ligand. A new approach to labelling hydroxyl-containing biomolecules.Figure optionsDownload full-size imageDownload as PowerPoint slide