Reaction of (Me3SiNSN)2S with palladium complexes; crystal structures of [PPh4]2[Pd2Br4(S3N2)] and [PPh4][PdBr2(S2N3)]

Abstract

Reaction of Me₃SiNSNSNSNSiMe₃ with [PPh₄]₂[Pd₂Cl₆] resulted in a mixture of [PPh₄][PdCl₂(S₂N₃)] and [PPh₄]₂[Pd₂Cl₄(S₃N₂)]; in addition to the analogous bromo species, reaction with [PPh₄]₂[Pd₂Br₆] also generated [PPh₄]₂[Pd₂Br₆(S₂N₂)]. The crystal structure of [PPh₄][PdBr₂(S₂N₃)], only the second full characterization of a complex of [S₂N₃]^–, confirmed the presence of two distinct S–N bond lengths (1.49 and 1.6 Å), while the ¹⁵N NMR spectrum of partially ¹⁵N-labelled [PPh₄][PdCl₂(S₂N₃)] confirms the absence of protonation on the S–N ligand. Potential mechanisms for these reactions are discussed.