New η-cycloheptatrienyl tungsten compounds and the intercalation of [M(η-C7H7)(η-C5H4Me)](M = Mo or W) into ZrS2
Abstract
The compound [W(η-C7H7)(η-C7H9)]1 is formed in gram quantities by reduction of WCl6 with sodium amalgam in the presence of cycloheptatriene. The compound 1 with iodine in acetonitrile gives [W(η-C7H7)(MeCN)I2]2 and this reacts with PMe3 forming [W(η-C7H7)(PMe3)I2]. Oxidation of 1 with bromine in acetonitrile yields [W(η-C7H7)(MeCN)Br2] and with bromine in tetrahydrofuran followed by addition of PMe3 gives [W(η-C7H7)(PMe3)Br2]. Reduction of 2 with sodium amalgam in the presence of 1,2-bis(dimethylphosphino)ethane (dmpe) affords [W(η-C7H7)(dmpe)I]. Compound 2 also reacts with Na(C5H4R)(R = H or Me) and lithium indenide to give the mixed-sandwich compounds [W(η-C7H7)(η-C5H4R)](R = H or Me) and [W(η-C7H7)(η-C9H7)] respectively. The sandwich compounds [M(η-C7H7)(η-C5H4Me)](M = Mo or W) and ZrS2 form the intercalates {ZrS2[M(η-C7H7)(η-C5H4Me)]x}.