Ruthenium pentacarbonyl

For catalyst combinations containing initial I/Ru ratios 5, the product solutions also show strong new bands at 1999 and 2036 cm characteristic (6) of ruthenium pentacarbonyl. Where acetic acid homologation is run at [RuJ > 0.2 M, then another ruthenium iodocarbonyl, Ru(C0)3I2, may be isolated from the product mix as a yellow crystalline solid. A typical spectrum of this material is illustrated in Figure 3b. 

Silylene 1 reacts with Fe(CO)s or Fe2(CO)9 to give the complex (l)Fe(CO)4, also reported earlier [2], With ruthenium pentacarbonyl, however, 1 reacts with removal of two CO groups, yielding (1)2Ru(CO)3 [9], This complex has an unusual unit cell containing two different structures. As shown in Fig. 5, both kinds of molecules have essentially a trigonal bipyramidal geometry, but in half of the molecules two CO groups occupy the (near) axial positions, and in the other half the silylenes take the (near) axial sites. 

Structure and Bonding in Transition Metal Carbonyls and Nitrosyls. 4. Molecular Structure of Ruthenium Pentacarbonyl Determined by Gas-Phase Electron Diffraction. 

It has been demonstrated that group 6 Fischer-type metal carbene complexes can in principle undergo carbene transfer reactions in the presence of suitable transition metals [122]. It was therefore interesting to test the compatibility of ruthenium-based metathesis catalysts and electrophilic metal carbene functionalities. A series of examples of the formation of oxacyclic carbene complexes by metathesis (e.g., 128, 129, Scheme 26) was published by Dotz et al. [123]. These include substrates where double bonds conjugated to the pentacarbonyl metal moiety participate in the metathesis reaction. Evidence is... 

The preparation of carbonylmetals by treating a transition metal halide either with carbon monoxide and zinc, or with iron pentacarbonyl is well-known and smooth. However, a violent eruptive reaction occurs if a methanolic solution of a cobalt halide, a rhodium halide or a ruthenium halide is treated with both zinc and iron pentacarbonyl. 

The mononuclear metal carbonyls contain only one metal atom, and they have comparatively simple structures. For example, nickel tetracarbonyl is tetrahedral. The pentacarbonyls of iron, ruthenium, and osmium are trigonal bipyramidal, whereas the hexacarbonyls of vanadium, chromium, molybdenum, and tungsten are octahedral. These structures are shown in Figure 21.1. 

When finely-divided Ru metal is heated with carbon monoxide under 200 atm pressure, ruthenium converts to pentacarbonyl, Ru(CO)5, a colorless liquid that decomposes on heating to diruthenium nonacarbonyl, Ru2(CO)g, a... 

F,MnO SC6, Manganese( I), pentacarbonyl-(trifluoromethanesulfonato)-, 26 114 F,0 CH, Acetic acid, trifluoro-tungsten complex, 26 222 F,02C,H, Acetic acid, trifluoro-ruthenium complex, 26 254 FjOjSCH, Methanesulfonic acid, trifluoro-iridium, manganese and rhenium complexes, 26 114, 115, 120 platinum complex, 26 126 F304PtSC,4H,5, Platinum(II), hydrido-(methanol)bis(triethylphosphine)-Irans-, trifluoromethanesulfonate,... 

F. Calderazzo, and F. L Eplattenier, The Pentacarbonyls of Ruthenium and Osmium. I. Infrared Spectra and Reactivity, Inorg. Chem. 6, 1220-1224 (1967). 

The pentacarbonyls of ruthenium(O) and osmium(O), M(C0)5 (M = Ru, Os), show two carbonyl stretching vibrations in the IR spectrum (heptane) at 2035s, 1999vs (Ru) and 2034s, 1991vs (Os) cm. On the basis of the number of IR-active bands observed, a trigonal bipyramidal structure of D h symmetry is suggested. 

Mono- and Dinuclear Compounds. The pentacarbonyl is a starting material for mononuclear ruthenium carbonyl complexes. As outlined in Scheme 3, reduction with sodium in liquid ammonia yields a pale-colored anion solution (5),... 

SAFETY PROFILE Poison by intraperitoneal route. Incompatible with iron pentacarbonyl and zinc. When heated to decomposition it emits toxic fumes of RuOx and Cr. See also RUTHENIUM COMPOUNDS. 

HYDROGENATION CATALYSTS Bis-(pyridine)dimethylformamidcdichlororbo-dium borohydride. Iron pentacarbonyl. Lindlar catalyst. Nickel boride. Palladium-on-calcium carbonate. Rhodium-on-alumina. Rhodium-on-carbon. Ruthenium trichloride hydrate. Triton dodecacar-bonyL Tris(tiiplienylpho ine)chloto-... 

Under comparable reaction conditions, the carbonylation of alkynes can be steered in another direction by varying the catalyst metals. For instance, using iron pentacarbonyl [25] or ruthenium carbonyl [26] as catalysts, the principal product is hydroquinone (eq. (11)). 

Iron pentacarbonyl and some ruthenium(III) complexes, such as RuCls 3 H2O or Ru(NH3)4(OH)Cl2, are claimed in a patent as catalysts for the hydroamination of ethylene and higher olefins in homogeneous solution [13]. 

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