Ruthenium tricarbonyl

While the ruthenium component is important and essential, the reasons for its behaviour are not always well understood. We will give some accounts of the chemical and catalytic properties of the ruthenium tricarbonyl triiodide species, [Ru(CO)3l3 ]", which is often the sole derivative detected in catalytic solutions under reaction conditions. This will contribute to a better understanding of the aspects of the catalytic behaviour and of the scope of catalytic capabilities. 

In analogy to the homologous iron complex 148c [Eq. (125)], ( -7V-methoxycarbonyl- H-azepine)ruthenium tricarbonyl reacts with HFA 127). 

Most recently, a new type of mononuclear/dinuclear ruthenium WGSR catalysis system was described by Shvo et al. [38]. The system is based on the reaction of tetraphenylcyclone (CPD) ruthenium tricarbonyl, (n" -CPD) Ru(CO)3 with OH . 

In accordance with FMO theory predictions,273 C2 —C4is the preferred modeofcycloaddition of tricarbonyliron and -ruthenium complexes of methyl l//-azepine-l-carboxylate with ethenetetracarbonitrile,222,274 hexafluoroacetone,222 and 2,2-bis(trifluoromethyl)ethene-l,l-dicarbonitrile 222 however, with ethenetetracarbonitrile, tricarbonyl[f/4-l-(ethoxycarbonyl)-1/f-azepine]iron(0) (1) yields a 1 6 mixture of the predicted C2 —C4 exo-adduct 2 and the C2 — C7 [6 + 2] 7i-cycloadduct 3,222 the latter heing formed by rearrangement of the former.274 Mixtures of the two adducts are also obtained with the tricarbonyliron complexes of 3-acetyl-l//-azepine and its l-(ethoxycarbonyl) derivative.274... 

Ursini, C.V., Dias, G.H.M. and Rodrigues, J.A.R., Ruthenium-catalyzed reduction of racemic tricarbonyl( 7 -aryl ketonejchromium complexes using transfer hydrogenation a simple alternative to the resolution of planar chiral organometallics. J. Organomet. Chem., 2005,690, 3176. 

HglOoRujCijH, Ruthenium, nonacarbonyl-(3,3-dimethyl-l-butynyl)-(iodomercury)-/Wangu/o-tri-, 26 330 HgMo012Ru3C23Hi4, Ruthenium, nonacar-bonyl-( x3-3,3-dimethyl-1 -butynyl) p.-[tricarbonyl(-ri -cyclopentadienyl)-molybdenum]mercury -/riangu/o-tri-, 26 333... 

The ruthenium carbonyl complexes [Ru(CO)2(OCOCH3)] n, Ru3(CO)12, and a new one, tentatively formulated [HRu-(CO)s ] n, homogeneously catalyze the carbonylation of cyclic secondary amines under mild conditions (1 atm, 75°C) to give exclusively the N-formyl products. The acetate polymer dissolves in amines to give [Ru(CO)2(OCOCH3)(amine)]2 dimers. Kinetic studies on piperidine carbonylation catalyzed by the acetate polymer (in neat amine) and the iiydride polymer (in toluene-amine solutions) indicate that a monomeric tricarbonyl species is involved in the mechanism in each case. 

Materials. Ruthenium trichloride was obtained as the soluble trihydrate from Johnson Matthey Ltd. Treatment of aqueous acetic acid-acetate solutions of the trichloride with 1 atm CO at 80 °C for about 10 hrs gives almost quantitative yields of the tricarbonyl dimer... 

The stoichiometric carbonylation observed using [HRu(CO)3] and the proposed catalytic schemes all involve tricarbonyl species as the active catalyst the relatively high activity of Ru3(CO)i2 is consistent with this. The relative activity of the complexes for piperidine carbonylation is [HRu(CO)3L Ru3(CO)12 > [Ru(CO)2(OCOMe)]n. The major cause of the decrease in carbonylation rates is the accumulation of formyl product although the decrease in amine concentration is also a contributing factor. This catalyst poisoning is likely attributable to com-plexation to the ruthenium, presumably via the carbonyl grouping as commonly found for formamide ligands (26). The product could compete with either amine or CO for a metal coordination site. 

Tricarbonyls with D h symmetry (see Table 9) occur commonly in complexes of the type Fe(CO)3(L)2 (and their ruthenium and osmium analogs). There are two v(CO) modes, an a[ symmetric stretch, which is inactive in the IR, and an e stretch. These two absorptions are sufficient to determine the two force constants. 

Ruthenium (3-5-q3-2-Cyan-5-dehy-dro-cycloheptenyl)-tricarbonyl-XlII/9a, 555... 

Described here is the preparation of (benzylideneacetone )tricarbonyliron-(0) and (l,5-cyclooctadiene)tricarbonyl ruthenium(0). Both compounds func-... 

In contrast to the very large number of tricarbonyl( -diene)iron complexes described in the literature,thg corresponding ruthenium compounds have received very little attention. This may reflect the well-documented tendency of ruthenium to form metal—metal bonds as opposed to iron. particular, while the metal—metal bonds in Fe3(CO)i2 are easily broken, Ru3(CO)i2 undergoes a variety of reactions in which the Rus cluster is retained. 

The complex functions as the most suitable source of the tricarbonylruthe-nium unit in syntheses of tricarbonyl(7-diene)ruthenium complexes. Derivatives of 1,3-cyclohexadiene, 1,3-cycloheptadiene, cycloheptatriene, cyclooc-tatetraene, 2,4,6-cycloheptatrien-l-one, bicyclo[3.2. l]octa-2,6-diene, bicyclo-[3.2. l]octa-2,4-diene, and butadiene have been prepared by displacement of 1,5-cyclooctadiene. 

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