Phosphonato-phosphinito peri-substituted naphthalenes

Two strained peri-substituted naphthalenes bearing phosphonate and phosphinite ester functionalities were synthesized and fully characterised. They both show repulsive interactions of the phosphorus moieties, however the balance of out-of-plane and in-plane distortions as well as sub-Van der Waals interactions is remarkably different for the two very similar molecules.