Activation of sp2 and sp3 carbon–hydrogen bonds via thermolysis of bis(η-cyclopentadienyl)hydridomethyltungsten

Abstract

The methylhydride [W(η-C₅H₅)₂Me(H)] has been prepared by treatment of the compounds [W(η-C₅H₅)₂MeX], where X = I or OCOPh, with Na[AlH₂(OCH₂CH₂OMe)₂]. Thermal decomposition of [W(η-C₅H₅)₂Me(H)] in benzene, fluorobenzene, p-xylene, trimethyl phosphite, methanol, or dimethyl (4-tolyl)phosphine evolves methane and the compounds [W(η-C₅H₅)₂R(H)], where R = Ph, C₆H₄F-3 or -4, CH₂C₆H₄Me-4, OP(OMe)₂, OMe, or PH(C₆H₄Me-4) are formed. Treatment of [W(η-C₅H₅)₂{PH(C₆H₄Me-4)}H] with methyl iodide gives [W(η-C₅H₅)₂{PH (Me)(C₆H₄Me-4)}H]⁺. The oxidation of [W(η-C₅H₅)₂Me₂]⁺ which may be reduced to the parent dimethyl compound.