Cluster Construction by Reactions of an Isomeric Pair of Trinuclear Clusters Containing a Tetrathiotungstate Fragment, [{Cp‘Ru(CO)}2{W(μ-S)4}] and [{Cp‘Ru(CO)}2{W(S)(μ3-S)(μ-S)2}] (Cp‘ = η5-C5Me5, η5-C5Me4Et), with Platinum Complexes

Abstract

The reactions of the isomeric pair of trinuclear clusters [{Cp‘Ru(CO)}2{W(μ-S)4}] (3) and [{Cp‘Ru(CO)}2{W(S)(μ3-S)(μ-S)2}] (4) with 1 equiv of [PtMe2(cod)] gave the respective tetranuclear clusters [{Cp‘Ru(CO)}2{W(μ3-S)2(μ-S)2}(PtMe2)] (5) and [{Cp‘Ru(CO)}2{W(S)(μ3-S)3}(PtMe2)] (6) (Cp‘ = η5-C5Me5 (=Cp*), η5-C5Me4Et) containing a tetrathiotungstate fragment as the main products, which corresponds to an isomeric pair. The pentanuclear cluster [{Cp‘Ru(CO)}2{W(μ3-S)4}(PtMe2)2] (7) was obtained by the reaction of [{Cp‘Ru(CO)}2{W(μ-S)4}] (3) with 2 equiv of [PtMe2(cod)]. Treatment of [{Cp*Ru(CO)}2{W(μ3-S)2(μ-S)2}(PtMe2)] (5a) with excess HCl underwent monochlorination of the methyl ligand in the PtMe2 moiety to give [{Cp*Ru(CO)}2{W(μ3-S)2(μ-S)2}(PtClMe)] (8) selectively. In the reaction of [{Cp*Ru(CO)}2{W(μ3-S)4}(PtMe2)2] (7a) with 1 equiv of HCl, monochlorination at one platinum center took place to give [{Cp*Ru(CO)}2{W(μ3-S)4}(PtClMe)(PtMe2)] (10) quantitatively, whereas the reaction of 7a with excess HCl took place with monochlorination at each platinum center to give [{Cp*Ru(CO)}2{W(μ3-S)4}(PtClMe)2] (9). The trinuclear cluster [{Cp‘Ru(CO)}2{W(μ-S)4}] (3) reacted with the platinum(0) complex [Pt(C2H4)(PPh3)2] to give the novel pentanuclear cluster [{Cp‘Ru(CO)}(WS4)(Cp‘Ru){Pt2(PPh3)2(μ-CO)}] (11). The product 11 has a new platinum−platinum bond bridged by a carbonyl ligand which is originally located on a ruthenium center. The tetrathiotungstate ligand in 11 bridges the ruthenium fragment Cp‘Ru(CO) and the three-membered metallacycle (Cp‘Ru){Pt(PPh3)}2(μ-CO).