The Anions [Cptt2Zr(μ-S)2M(CO)2]- (M = Rh, Ir) as Versatile Precursors for the Synthesis of Sulfido-Bridged Early−Late Heterotrimetallic (ELHT) Compounds†

The reaction of [Cptt2Zr(μ3-S)2{Ir(CO)2}2] (Cptt = η5-1,3-di-tert-butylcyclopentadienyl) with dppe (1,2-bis-(diphenylphosphino)ethane) affords the ion-pair compound [Ir(CO)(dppe)2][Cptt2Zr(μ-S)2Ir(CO)2] (2). The related compound [Rh(dppe)2][Cptt2Zr(μ-S)2Rh(CO)2] (5) has been obtained in solution under a carbon monoxide atmosphere by reaction of [Cptt2Zr(μ3-S)2{Rh(CO)2}2] with dppe through the intermediate heterotrinuclear compound [Cptt2Zr(μ3-S)2{Rh(dppe)}{Rh(CO)2}] (4). Reaction of the heterodinuclear anion [Cptt2Zr(μ-S)2Ir(CO)2]-, generated in situ, with [Rh(μ-Cl)(cod)]2, [RhCl2(CO)2]- and [Pd(μ-Cl)(η3-C3H5)]2 affords the d0−d8−d8 early−late compounds [Cptt2Zr(μ3-S)2{Ir(CO)2}{Rh(cod)}] (6), [Cptt2Zr(μ3-S)2{Ir(CO)2}{Rh(CO)2}] (7), and [Cptt2Zr(μ3-S)2{Ir(CO)2}{Pd(η3-C3H5)}] (8) each with a symmetrical trigonal−bipyramidal M3(μ3-S)2 heterotrimetallic metal−sulfur core. In the same way, the reaction of [Cptt2Zr(μ-S)2M(CO)2]- (M = Rh, Ir) with [AuCl(PPh3)] leads to the preparation of the d0−d8−d10 early−late compounds [Cptt2Zr(μ-S)2{Ir(CO)2}{Au(PPh3)}] (9) and [Cptt2Zr(μ-S)2{Rh(CO)2}{Au(PPh3)}] (10) with an open M3(μ3-S)(μ2-S) heterotrimetallic metal−sulfur framework. On the other hand, treatment of the bis(hydrosulfido)zirconium compound [Cptt2Zr(SH)2] with triethylamine followed by addition of [Pd(μ-Cl)(η3-C3H5)]2 or [AuCl(PPh3)] affords the sulfido-bridged early−late heterobimetallic compounds [Cptt2Zr(μ3-S)2{Pd(η3-C3H5)}2] (11) and [Cptt2Zr(μ-S)2{Au(PPh3)}2] (12). The molecular structure of complexes 9 and 12 determined by X-ray diffraction methods are also described.