Stereoselectivity in Reactions of Metal Complexes. Part XI. 2,6-Bis(pyrrolidin-2-yl)pyridine: Synthesis and resolution of the meso and the optically active isomers. Complex formation with copper(II) ion in aqueous solution

The new linear triamine 2,6-bis(pyrrolidin-2-yl)pyridine ( II ) has been synthesized, and the (R, S)-, (R, R)-, and (S, S)-isomers have been separated. Compared to other triamines showing a similar structure, these new ligands form very stable Cu²⁺ complexes. No significant difference is observed between the meso and the racemic forms for their binary or ternary mixed-ligand complexes with the amino acids alanine and proline.