LAUSR

This mini-review describes a broad spectrum of synthetic strategies to access mono- and polycyclic azaphosphiridines; properties and theoretical calculations of free and metal-ligated are discussed. These species are characterized by a highly strained (saturated) CPN ring with three differently polarized endocyclic bonds. The latter causes a high reactivity of aza-phosphiridine complexes towards ring expansion and exchange reactions. Increasing the ring strain leads to masked FLP behaviour, i.e., small molecule activation was observed. New perspectives in homogenous catalysis are also offered, e.g., a pool of novel chiral P-heterocyclic ligands, ready to be explored, if the challenge to unligate them is solved.