1,2-Diphosphinobenzene as a synthon for the 1,2,3-triphospha- and 2-arsa-1,3-diphosphaindenyl anions and a stable organo derivative of the P8 unit of Hittorf’s phosphorus

Abstract

The electronic structure of the 1,2,3-triphosphaindenyl ligand suggests that it should exhibit enhanced π-acceptor properties when compared to the η⁵-indenyl system; this insight encouraged us to develop a simple synthetic pathway from 1,2-diphosphinobenzene to the 1,2,3-C₆H₄P₃ and 2-As-1,3-C₆H₄P₂ anions, both of which have been structurally characterised by X-ray crystallography; as a bonus from these studies we also obtained the first structurally characterised organo derivative of the P₈ unit present in Hittorf’s phosphorus.