Bis(bidentate) complexes of iminobis(diphenylphosphine chalcogenides)[M{N(XPPh2)2-X,X′}2](X = S or Se; M = Ni, Pd or Pt)

The compound NH(SePPh(2))(2) has been synthesised from NH(PPh(2))(2) and selenium in refluxing toluene. A range of complexes [M{N(XPPh(2))(2)-X, X'}(2)] (X = Se, M = Pt 1 or Pd 2; X = S, M = Pt 3, Pd 4 or Ni 5) of the monoanions derived from NH(SePPh(2))(2) and its sulfur analogue have been prepared. The new compounds have been characterised by microanalysis, NMR and IR spectroscopy. The crystal structures of NH(SePPh(2))(2), 1, 2 and 5 were determined. The neutral NH(SePPh(2))(2) crystallised as H-bonded dimer pairs with a noticeable difference in the hydrogen bonded End nonhydrogen bonded P=Se bond lengths. The P=Se groups are approximately anti. On complexation the anionic ligands are bidentate and in all cases the resulting MX(2)P(2)N rings are distinctly puckered.