Mixed-metal cluster chemistry.: Part 17. Syntheses of WIr3(CO)11(η-C5H4Me) and its reactivity towards diphenylacetylene

The X-ray structurally confirmed tetrahedral mixed-metal cluster WIr3(CO)11(η-C5H4Me) (1) is prepared in 8% yield from reactions between [W(CO)3(η-C5H4Me)]− and IrCl(CO)2(p-toluidine) under an Ar atmosphere, and in 46% yield from reaction between WH(CO)3(η-C5H4Me) and IrCl(CO)2(p-toluidine) under a CO atmosphere; both reactions also afford tetrahedral W2Ir2(CO)10(η-C5H4Me)2 (2). Cluster 1 reacts with diphenylacetylene to afford three products, namely tetrahedral WIr3(μ3-η2-PhC2Ph)2(CO)7(η-C5H4Me) (3), butterfly WIr3{μ-η4-C(Ph)C(Ph)C(Ph)C(Ph)}(CO)5(η-C5H4Me) (4) and the binuclear product Ir2{μ-η4-C(Ph)C(Ph)C(Ph)C(Ph)}(CO)5 (5); X-ray studies of 4 and 5 reveal a common (iridacyclopentadienyl)iridium structural motif.