The Aromaticity of Phosphorus Compounds

Abstract
By using photoelectron spectroscopy and ab initio quantum-chemical methods it has been revealed that phosphorus is capable to build cyclic, stabilized, conjugated systems in any of its oxidation state, including σ23-, σ33-, σ35- as well as σ45-P. The conjugative ability of phosphorus - as shown on π-ionization energies and stabilization energies in isodesmic reactions - is similar to that of carbon.