An inorganic heterocycle containing an exocyclic sulphur–iodine bond: synthesis and X-ray crystal structure of (Ph2PN)2NSI and its thermal conversion into a spirocyclic P4SN6 ring

Abstract

The reaction of (Ph₂PN)₂NSCI with KI in acetonitrile produces (Ph₂PN)₂NSI which is shown by X-ray crystallography to contain a six-membered P₂SN₃ ring with an exocyclic S–I bond; the thermal decomposition of (Ph₂PN)₂NSI leads to Ph₈P₄SN₆, a spirocyclic compound in which two P₂SN₃ rings share a common sulphur atom.