W/Cu(Ag)/S complexes containing bridging diphosphine ligands: Synthesis, structures and optical properties

Abstract

The substitution reactions of [Et 4N] 2[WOS 3MCN] (M = Cu, Ag) with dppe (dppe = 1,2-bis(diphenylphosphino) ethane) in DMF afforded a tetranuclear cluster [Et 4N] 2[WOS 3Cu(dppe)] 2 · H 2O ( 1) and a polymer [WEE′S 2Ag(dppe)] 2 · CH 3CN ( 3) (E = 0.636S + 0.364O, E′ = 0.581O + 0.419S), respectively. Treatment of 1 with AgI at elevated temperature yielded polymeric complex [WS 4Cu 2(dppe) 2] n ( 2). X-ray single crystal structural analyses revealed that in both 1 and 2, the W/Cu/S cluster units are linked by two dppe ligands to form a 10-membered [–Cu–P–C–C–P–] 2 ring. In the polymeric structure of 2, the W and Cu atoms form a helical chain whereas in 3 the cluster units (WEE′S 2Ag) are bridged by dppe ligands affording a zig-zag chain structure. The optical absorption spectra and the solid-state photoluminescent properties of the title complexes are also studied.