Since the LUMOs of nontrigonal pnictogen compounds consist mainly of the vacant p orbitals of the pnictogen nuclei, they could undergo one-electron reduction to afford radical anions if the energy levels of LUMOs are appropriate. For a less sterically hindered compound, the generated radical anion readily dimerizes to form a dianion with a P-P bond. When a sterically encumbered tris-amide ligand is used, stable radical anions bearing T-shaped pnictogen nuclei can be isolated and characterized.
The oxidation of nontrigonal phosphorus compounds and transfer of halogen molecules to the phosphorus atoms to generate phosphoranes with phosphorus atoms in an oxidation state of +5 was achieved by various synthetic procedures. These dihalides are promising starting materials and potentially applicable for the generation of numerous secondary products, but only few reactions have been reported so far in the literature. Nontrigonal phosphorus compounds can also be oxidized by organic azide to yield phosphazenes.