The first structurally characterised cyclotriphosphazene substituted with a sulfonamide nitrogen

The reaction between two equivalents of N-(2-hydroxyphenyl)-p-toluenesulfonamide (H2sulf) and [N3P3(biph)2Cl2] (H2biph = 2,2′-biphenol) produces the compound bis(2,2′-biphenylato)bis(2-oxyphenyl)-p-toluenesulfonamide cyclotriphosphazene (H2L) containing two geminal Hsulf moieties. Further reaction of H2L in basic conditions results in the removal of the sulfonamide arm and the slow formation of a novel phosphazene containing the spirocyclic sulf moiety. When this occurs in the presence of [Pd(bpy)Cl2] the reaction is facile and the new complex [Pd(bpy)(sulf)] (2) is also formed. Compounds H2L, 1 and 2 have all been characterised by single crystal X-ray crystallography.