Reaction of the [mu]-isophosphaalkyne complex ([eta]5-C5H5)2 (CO)2([mu]-CO)Fe2([mu]-CPMes) (Mes = 2,4,6-Me3C6H2) (2a) with [(Z)-Cyclooctene]Cr(CO)5 or Fe2(CO)9 gives rise to the [mu]3-isophosphaalkyne complexes ([eta]5-C5H5)2(CO)2([mu]-CO)Fe2{[mu]-CP[M(CO)n]Mes} 3a [M(CO)n = Cr(CO)5] and 4a [M(CO)n = Fe(CO)4]. Similarly ([eta]5-C5H5)2(CO)2([mu]-CO)Fe2{[mu] -CP[Cr (CO)5]C6H2(CF3)3-2,4,6} (3d) is obtained. The metal carbonyl fragments are attached to 2 in a [eta]1-fashion by the lone-pair at the phosphorus. In contrast to this the treatment of 2a with (Ph3P)2Pt([eta]2-C2H4) affords complex 5a in which 2a serves as an [mu]3-3e ligand towards the PtPPh3 moiety. The molecular structures of 3a and 5a are determined by single-crystal X-ray analysis.