Synthesis and crystal structures of new palladium–sulfur–nitrogen complexes

Abstract

The compound S₄N₄ reacts with [PPh₄]₂[Pd₂X₆](X = Cl or Br) in CH₂Cl₂ to give a mixture of [PPh₄]₂[Pd₂(µ-S₂N₂)X₆],[PPh₄]₂[Pd₂(µ-S₃N₂)X₄] and [PPh₄][Pd(S₂N₂H)X₂]. Reaction of [PPh₄]₂[Pd₂I₆] with S₄N₄ in the same solvent yields an insoluble solid of empirical formula [PPh₄][Pd₂S₆N₆I₃]. All these reactions were investigated by ¹⁵N NMR spectroscopy using samples prepared from S₄¹⁵N₄. Thermolysis of [PPh₄]₂[Pd₂(µ-S₂N₂)Cl₆] in CHCl₃ gives an alternative polymorph (β form) of this, whereas photolysis causes the species to decompose. The crystal structures of [PPh₄][Pd(S₂N₂H)Cl₂], β-[PPh₄]₂[Pd₂(µ-S₂N₂)Cl₆] and [PPh₄]₂[Pd₂(µ-S₂N₂)Br₆] have been determined.