Synthesis and spectral studies on some arylchalcogen/chloro/telluroamine bridged heterobimetallic complexes of d8 ions

Abstract

The compounds [(N,Te)M(ClO 4) 2] ( Ia, IIa), [(N,Te) 2M](ClO 4) 2( Ib, IIb) and [(N,Te) 2MCl 2] ( Ic, IIc) have been obtained from [(N,Te)MCl 2] ( I, II) [M Pd ( I), Pt ( II) and N,Te 1-(NMe 2)-2-(TeC 6H 4OEt)-4-Me-C 6H 3)] by the action of AgClO 4 subsequently followed by the addition of excess (N,Te) ligand and then KCl. The metallo-ligand [(N,Te)M(EAr) 2] (E Se,Te; Ar Ph,C 6H 4-4-OMe), generated in situ from I or II by the action of EAr − reacts with Pt(PhCN) 2Cl 2, Pd(PhCN) 2Cl 2 and Ni(dppe)(ClO 4) 2 to give heterobimetallic complexes of the types: [(N,Te)Pd(μ-PhSe) 2PtCl 2] ( III), [(N,Te)Pt(μ-PhTe) 2PdCl 2] ( IV) and [(dppe)Pt(μ-ArTe) 2Ni(N,Te)](ClO 4) 2 ( V) (dppe diphenylphos-phinoethane), respectively. The reaction of the compound IIa with Ni(dppe)Cl 2 results in [(dppe)Pt(μ-Cl) 2Ni(N,Te)](ClO 4) 2 ( VI) via the formation Of [(ClO 4) 2Pt(μ-N,Te)(μ-dppe)NiCl 2] as an intermediate. The reactions of the compounds Ic and IIc with Ni(ClO 4) 2 in MeOH lead to the formation of[Cl 2Pd(μ-N,Te) 2Ni(ClO 4) 2] ( VII) and [Cl 2Pt(μ-N,Te) 2Ni(ClO 4) 2] ( VIII). The ring opening of the chelated dppe-nickel complex followed by complete transfer of dppe from nickel to platinum is observed for the first time. All these complexes have been characterized on the basis of their elemental analyses, conductance and molecular weight measurements, IR, UV-vis and NMR ( 1H, 31P, 125Te and 195Pt) spectra. The results of these studies are discussed.