Complexes with functional phosphines. XVII. Synthesis and characterization of ruthenium clusters with ketophosphine ligands. Crystal structure of the cluster 1(O):η2(P,O)-O(CPh)CHPPh2>(CO)9 containing a bridging phosphinoenolate ligand

Article abstract of DOI:10.1016/0022-328X(92)83137-7

Reactions of the ketophosphine Ph2PCH2C(O)Ph(P-O) with afforde the derivatives (1) and (4).In the presence of triphenylphosphiniminium acetate (PPN)(OAc), the former leads to the labile >> (2), in which the functional phosphine acts as a (P,O) bridging ligand, whereas thermal activation of either 1 or 4 results in PC-H bond cleavage and formation of 1(O):η²(P,O)-O(<*>CPh)-CHPPh2>(CO)9> (3) whose crystal structure reveals an unprecedented bonding mode f<*>r the phosphinoenolate ligand, its oxygen atom bridging the Ru(1)-Ru(2) edge.Protonation of this complex occurs selectively at the enolato-carbon and (CO)10>BF4 (5) and 2(CO)8>BF4 (7) were characterized in which the <*> ligand(s) bridge between two Ru centres.