Phosphorinanes as Ligands for Palladium-Catalyzed Cross-Coupling Chemistry

Phosphorinanes are presented as a class of phosphine ligand suitable for organopalladium cross-coupling chemistry. Prepared via a direct double Michael addition of a monoalkyl- or arylphosphine to phorone followed by a Wolf−Kishner reduction, phosphorinanes are relatively inexpensive to manufacture and allow modification of one of the alkyl moieties permitting steric and electronic fine-tuning of the ligands. Library screening and applications of these ligands in the Suzuki, Sonogashira, ketone arylation, and aryl amination reactions are presented.