OXIDATION OF METAL CARBYNES IN THE PRESENCE OF ALKYNES - ALKYNE ADDITION VS H-SHIFT IN THE CARBENE INTERMEDIATE

One-electron oxidation of the carbyne complex (eta(5)-C5H5)(CO){P(OPh) (3)}Mo=CCH2CH2CH2CH3 (1a) in the presence of phenylacetylene results i n H-abstraction and addition of the alkyne to the resulting metal carb ene. The final product of the addition is the eta(1)eta(2)-allyl compl ex ta(2)-CH{P(OPh)(3)}C(Ph)=CH(Ch(2)CH(2)CH(2)CH(3))] (2a), the struct ure of which was confirmed by X-ray crystallography.