Reaction of the diphosphene ArPPAr (Ar = 2,4,6-Bu t 3 C 6 H 2 ) with sulphur: isolation and X-ray structure of the diphosphene monosulphide

The diphosphene ArPPar (Ar = 2,4,6-But3C6H2) reacts with elemental sulphur to give the stable monosulphide ArP(S)Par (2) whose structure was confirmed by an X-ray analysis; when treated with hexamethylphosphorous triamide, (2) reverts to the starting diphosphene but thermal and photochemical isomerisation of (2) gives the thiadiphosphirane Ar[graphic omitted]Ar.