Abstract: 12 new diarylacet ylenedicobalt hexacarbonyl complexes were synthesized by complexation reaction of a-naphthyl,a-thienyl or sub-stituted-phenyl phenylacetylene with Co₂CO)₈ and N-acetylation of p-aminophenyl phenylacetylenedicobalt hexacarbonyl.The structures of all the complexes were characterized by elemental analysis,IR and ¹H NMR spectroscopy.Making a comparison between the N-acetylation of p-aminophenyl phenylacetylenedicobalt hexacarbonyl and that of aniline under comparable conditions,we found that the clustercore PhC₂Co₂(CO)₆ para to an amino group attached to aromatic ring does not obviously affect the nucleophilicity of aniline.