Synthesis of Ferrocenyl Diphosphine Ligands: Substitution of α-Methoxy or α-Dimethylamino Groups by Phosphines. Retention versus Inversion: A Stereochemical Study

The stereochemical course of the exchange reaction of α-methoxy or α-dimethylamino groups by phosphines in acetic acid has been studied for ferrocene derivatives that have either a ferrocenylethyl or a benzylferrocenyl backbone. The reaction proceeded with either retention or inversion of configuration depending on the substrate stereoisomer used. The parameters that influence the stereochemical course of these reactions, such as relative configuration or substitution patterns, are discussed.