Synthesis of tetranuclear mixed-metal clusters via the reaction of [Co(CO)4]- with closed metal carbonyl trimers. Crystal and molecular structure of [(Ph3P)2N][CoRu3(CO)13]

The new clusters HCoRu3 (CO)13, HCoRu2Os(CO)13, HCoRuOs2(CO)13, and HCoOs3(CO)13 have been synthesized by allowing K(Co(CO)4) to react with Ru3(CO)12, Ru2Os(CO)12, RuOs2(CO)12, and Os3(CO)12, respectively, followed by protonation. Reaction of KCo(CO)4 with Fe3(CO)12, Fe2Ru(CO)12, and FeRu2(CO)12 followed by acidification did not lead to the desired hydrido mixed-metal clusters but instead to various other products. Reaction of (PPN) (Co(CO)4) (PPN= (Ph3P)2N) with Fe3(CO)12 and Ru3(CO)12 without subsequent acidification gave the salts (PPN) (CoFe3(CO)13) and (PPN) (CoRu3(CO)13). The latter was structurally characterized by single crystal X-ray. It crystallizes in the space group P1 with Z= 2 and unit cell dimensions a = 9.783(5) Angstrons, b = 14.768(5) Angstrons, c = 18.675(5) Angstons, Alpha = 110.39(3) deg, Beta = 99.02(4) deg, Gamma = 91.44(4) deg, and V = 2489(4) Angstrons 3. Diffraction data (0 deg 20 50 deg) were collectedwith an Enraf-Nonius CAD4 automated diffractometer, using graphite-monochromat ized MoK Alpha radiation, and the structure was refined to R = 0.036 and RW = 0.044 for 6150 independent reflections with I greater than or equal to 3.0 sigma (I). The molecule contains a tetrahedral CoRu3 core with each Ru atom bonded to three terminal carbonyls, the Co atom bonded to one terminal carbonyl, and with a carbonyl ligand bridging each of the three Co-Ru bonds. Analogous reactions of (PPN) (Co(CO)4) with Fe2Ru(CO)12 and FeRu2(CO)12 gave products formulated as (PPN) (CoFe2Ru(CO)13) and (PPN) (CoFeRu2(CO)13) but these salts were not obtained pure. (Author)