Phosphorus-Nitrogen Compounds. Part Xliv.1cyclodiphosph(v)azanes Derived From Tri-Alkylphosphorothioic Triamides

N, N', N'-Tri-alkylphosphorothioic triamides, P(S)(NHR)3. R = Me, Et, Pr n , Pr i , Bu n , Bu n , Bu i , Ch2Ph, cyclopentyl and cyclohexyl, decompose at 190–240°C to give cyclodiphosph(V)azanes, [RHNP(S)NR]2. The 1H nmr spectra of the cyclic dimers are reported; trans-structures are assigned to the products R = Et, Pr n , Bu n , Bu i , and CH2Ph.