Synthesis and coordination chemistry of macrocyclic phosphine ligands

Macrocyclic phosphine compounds are sought after as ligands for transition metal complexes because of their strong binding properties. As such, these ligands are particularly useful in applications where robust transition metal–phosphine complexes are employed, as in homogeneous catalysis or in radiopharmaceuticals. This review summarizes the development of macrocyclic phosphine ligands, including their preparation and coordination to transition metals. Synthetic methods for the preparation of phosphine macrocycles are discussed, including methods for controlling ring size and stereochemistry. The coordination chemistry of macrocyclic phosphines is also reviewed. Many phosphine macrocycles are synthesized by template methods, and methods for removing the templating metal from the macrocyclic ligand are reviewed.

• New self-assembling macrocyclic phosphines.
• Control of stereochemistry using phosphole or phosphinine macrocycles.
• Template synthesis of facially coordinating triphosphine macrocycles.
• Synthesis and demetallation of tetraphosphine macrocycles around copper(I) templates.