Solid state conformational classification of eight-membered rings in copper complexes double bridged by phosphate, phosphonate or phosphinate ligands

A statistical classification of the solid state conformation in the title complexes using data retrieved from the Cambridge Structural Database (CSD) has been made. Phosphate and phosphinate complexes show a chair conformation preferably. In phosphonate complexes, the most frequent conformations are found to be boat–chair, chair and boat–boat; in all the boat–chair cases, the phosphorus atoms appear connected by a bridging carbon atom.