The interaction of Ru(OAc)2(Ph3P)2 with one equivalent of N,N'-bis[o-(di-phenylphosphino) benzylidene]ethylenediamine (P2NzC2) in refluxing dichloromethanc gave trans-Ru(OAc)2(PzN2C2)'2H20 (I) in moderate yield (63%); in refluxing-toluene, it gave a red solid which upon recrystallization in CHC13 gave trans-RuC12(P2NzC2)" 2H20 (II) in good yield (92%). Compound II could also be prepared in good yield (85%) via the interaction of RuCI2(DMSO)4 with one equivalent of P2NzC2 in refluxing toluene. The interaction of RuCI2(DMSO)4 with one equivalent of N,N'-bis[o-(diphenylphosphino) benzylidene]- 1,3-diaminopropane (P2N2C3), N,N'-bis[o-(diphenylphosphino)benzyl] ethylenediamine (P2N2C2H4) and N,N'-bis[o-(diphenylphosphino)benzamido]ethane (P2N2C2-amide) in refluxing toluene gave trans-RuCl2(P2N2C3) (Ⅲ), trans-RuC12(P2N2C2H4) (IV) and trans-RuC12(P2N2C2-amide) (V) in good yield, respectively. The interaction of Fe(C104)2" 6H20 with one equivalent of P2N2C2 and P2N2C2H4 in refluxing acetonitrile gave trans-[Fe(P2N2C2)(CH3CN)2](CI04)2 (VI) and trans-[Fe(P2N2C2H4) (CH3CN)2](CIO4)2 (VII), respectively. Interaction of FeC12-4H20 with one equivalent of N,N'-bis[o-(diphenylphosphino)benzylidene]-l,6-diaminohexane (P2N2C6) in refluxing gave trans-FeC12(P2N2C6) (VIII). Complexes I-VIII have been fully characterized by ana-lytical and spectroscopic methods. The structure of IV has been established by an X-ray diffraction study. Compound II could be reduced to compound IV with NaBH4 in ethanol and oxidized to V with aqueous H202 acetonitrile. Catalytic studies showed that both Ⅱ and IV were effected catalysts for the hydrogenation of acrylic acid to propionic acid.