The reaction of [Pt2X2(μ-Cl)2(PR3)2] with NaSpy or NaSepy gave complexes of the type [PtX(Epy)(PR3)]n (X=Cl or Ar; E=S or Se; PR3=PEt3, PMe2Ph, PMePh2 or PPh3; n=1 or 2) which were characterized by elemental analysis and by 1H, 31P{1H}, 195Pt{1H} n.m.r. spectroscopy. When X=Cl a dynamic equilibrium between [Pt2Cl2(μ-Spy)2(PR3)2] and [PtCl(k-S,N-Spy)(PR3)] species exists in CHCl3 solution. The aryl derivatives, X=Ar, exist exclusively as dimers (n=2) with predominantly S∩N bridging. The [Pt(Spy)2 (PPh3)2] complex, prepared by reacting [PtCl2 (PPh3)2] with NaSpy, dissociates in CHCl3 to [Pt(k-S,N-Spy) (Spy)(PPh3)] and PPh3 at room temperature.