Reaction of [PPN][Fe3(CO)CCOC(O)CH3] with the Metal Nucleophile [Re(CO)5]- To Generate a Mixed-Metal Acetylide, [PPN][Fe3(CO)9CCRe(CO)5]

The cluster [PPN][Fe3(CO)9CCOC(O)CH3], 2, reacts with [PPN][Re(CO)5] to generate a metalated acetylide species, [PPN][Fe3(CO)9CCRe(CO)5], 3, which was characterized by infrared and 13C NMR spectroscopy. A byproduct of this reaction, [PPN]2[Fe3(CO)9CCO], appears to result from the attack of [Re(CO)5]- on the acyl carbon in compound 2, and a strategy was devised to suppress this side reaction. The structure of 3 was determined by single-crystal X-ray diffraction. The central C−C bond distance is 1.28(1) A.