REACTIVITY OF PHOSPHINOALKYNES TOWARD [HFE3(CO)9(C=CH2)]-

The reactions of triphenylphosphine and (diphenylphosphino)alkynes Ph2P = R (R = CH3, C6H5, C6H4CH3, C(CH3)3) or C(O)OCH3) with [PPh4] [HFe3(CO)9(mu-3-eta-2-C = CH2)] have been studied. The complexes [PPh4] [Fe3(CO)9(mu-3-CCH3)L] (L = PPh3 or Ph2PC = CR) were isolated in high yields. The reaction involves migration of hydride which transforms the vinylidene ligand into an ethylidyne ligand. (Diphenylphosphino)alkynes are coordinated to metal atoms only through the phosphine centre and the alkyne group remains uncoordinated. The reaction of the new complexes with Co2(CO)8 has been studied.