| abstract |
Process for the preparation of metal salenes by reacting an optionally optically or multiply substituted optionally optically active salicylaldehyde with an optionally optically active diamine or an amine at elevated temperature in a suitable solvent and subsequently reacting the obtained salt with a metal compound, which is characterized in that that a metal (II) oxide is used as the metal compound. Of particular importance are cobalt salenes, such as salcomin, known as an oxidation catalyst, and optically active manganese salenes as catalysts for asymmetric epoxidations of olefins. DOLLAR A The surprisingly found possibility of using the metal oxides obtained in the combustion of metal-containing distillation residues directly again for the production of metal salenes opens up a technically interesting route to the metal salenes while avoiding waste containing heavy metals. |