Synthesis and structures of isomeric diphenylphosphinoamino-substituted cyclodiphosph(III)azanes

The chemistry of the cyclodiphosph(III)azanes (1) (R = alkylamino, alkoxy ; R' = alkyl, aryl, Me3Si) has recently formed the subject of several investigations, with the effects of geometrical isomerism and the relationship with the phosph(III)azenes, RP=NR', receiving special attention. So far, only relatively simple amino- or silylamino-derivatives have been obtained, but we have now synthesized a diphenylphosphino-derivative (2), which is a tetraphosphine, and examined its solution and solid-state structure