Reactions of [(η6-Me6C6)Ru(Ph2PCHCH2)Cl2] with 1-ethynylcycloalkanols leading to methoxy-alkenyl carbenes via vinylvinylidene and/or allenylidene intermediates

Methoxy-alkenyl carbenes 1 and 2 have been synthesized by treating a dichloro-methane/methanol solution of the [(η6-Me6C6)Ru(Ph2PCHCH2)Cl2] complex with an excess of 1-ethynyl-1-cyclohexanol and 1-ethynyl-1-cyclopentanol in the presence of NaPF6. The compounds were characterized by IR and 1H, 13C{1H}, 31P{1H} NMR spectroscopies and by elemental analyses. The crystal structure of 2 has also been determined by X-ray crystallography.