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Heterobimetallic complexes with metal-metal bonds supported by bridging donor-functionalized cyclopentadienyl ligands facilitate reactions at metal-metal bonds that would likely afford homolytic or heterolytic M-M’ bond cleavage without the kinetic stabilization afforded by the bridging ligand.  Reactions of neutral allylpalladium(II) complexes with free radicals resulting in reductive elimination of alkenes prompted us to synthesize heterobimetallics with (allyl)M fragments (M = Ni, Pd) bridged by (2-(diphenylphosphino)ethyl)cyclopentadienyl (Cp^PPh) group VI metal tricarbonyl metalloligands.  The (2-methylallyl)nickel complexes M’{Ni(eta-3-C₄H₇)}(CO)₃(eta-5:eta-1-Cp^PPh) (M’ = Cr (1), Mo (2), W (3)), (cyclohexenyl)nickel complexes M’{Ni(eta-3-C₆H₉)}(CO)₃(eta-5:eta-1-Cp^PPh) (M’ = Cr (4), Mo (5), W (6)) and analogous (allyl)palladium complexes M’{Pd(eta-3-C₃H₅)}(CO)₃(eta-5:eta-1-Cp^PPh) (M’ = Cr (7), Mo (8), W (9)) were synthesized by salt elimination reactions.  The formulations of 1-9 as heterobimetallics containing group VI-group X bonds supported by bridging Cp^PPh ligands were established in the solid-state by single crystal X-ray crystallography.  Aaron Heerboth ’08 and the PI carried out this research during spring and summer 2008.  This research opportunity and previous published work funded by this award aided Aaron Heerboth's matriculation in an M.D./Ph.D. program at Weill Cornell Medical College.  This synthetic work sets the stage for reactivity studies of 1-9 to target transformations at the coordinated allyl ligands.  Ligand-based reactivity is a new research area for this PI; PRF support is critical to permit his professional development in this vital organometallic chemistry subfield.  The PI was on sabbatical at UC-Berkeley during the 2008-2009 academic year; this narrative summarizes our work supported by PRF #46626-B3 as of August 2008.