Ruthenium, dichloro

Ruthenium, [l,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(phenylmethylene) (tricyclohexylphosphine)-,... 

Scheme 3 shows the details of the synthetic strategy adopted for the preparation of heteroleptic cis- and trans-complexes. Reaction of dichloro(p-cymene)ruthenium(II) dimer in ethanol solution at reflux temperature with 4,4,-dicarboxy-2.2 -bipyridine (L) resulted the pure mononuclear complex [Ru(cymene)ClL]Cl. In this step, the coordination of substituted bipyridine ligand to the ruthenium center takes place with cleavage of the doubly chloride-bridged structure of the dimeric starting material. The presence of three pyridine proton environments in the NMR spectrum is consistent with the symmetry seen in the solid-state crystal structure (Figure 24). 

R)-(-)-Methyl 3-hydroxybutanoate Butyric acid, 3-hydroxy-, methyl ester, D-(-)-(8) Butanoic acid, 3-hydroxy- methyl ester, (R)- (9) (3976-69-0) [(R)-2,2 -Bls(dlphenylphosphino)-1,1 -binaphthyl]dichlororuthenium Ruthenium, [[1,1 -binaphthalene]-2,2 -diylbis(diphenylphosphine)-P,P ]dichloro- (12) (115245-70-0)... 

The dichlororuthenium arene dimers are conveniently prepared by refluxing ethanolic ruthenium trichloride in the appropriate cyclohexadiene [19]. The di-chloro(pentamethylcyclopentadienyl) rhodium dimer is prepared by refluxing Dewar benzene and rhodium trichloride, whilst the dichloro(pentamethylcyclo-pentadienyl)iridium dimer is prepared by reaction of the cyclopentadiene with iridium trichloride [20]. Alternatively, the complexes can be purchased from most precious-metal suppliers. It should be noted that these ruthenium, rhodium and iridium arenes are all fine, dusty, solids and are potential respiratory sensitizers. Hence, the materials should be handled with great care, especially when weighing or charging operations are being carried out. Appropriate protective clothing and air extraction facilities should be used at all times. 

Experimental Procedure 3.1.3. Preparation of a Ruthenium Carbene Complex from a Diazoalkane Dichloro-bis(tricyclohexylphosphine)benzylideneruthenium... 

In an extensive study of the isomerization of hexenes and heptenes by platinum, palladium, and ruthenium, Harrod and Chalk (65) found that in many cases the equilibrium mixture of isomerized olefins was obtained. Isomerizations were achieved with Pt(II) (as 1,3-bisethylene-2,4-dichloro-fi-dichlorodiplatinum(II) with alcohol as cocatalyst), Pd(II)... 

Dichloro(3,3-diphenyl-2-propenylidene)-6 s-(triphenylphosphine)-ruthenium (compound 22) ... 

Whereas d ruthenium complexes add protic nucleophiles to the C3=C4 of the butatrienylidene ligand to give alkenylallenylidene complexes (see Scheme 3.22), iridium complex 11 adds trifluoroacetic add to the C2=C3 bond to form an alkenylvinylidene complex [2, 3]. The corresponding reaction of 11 with two equivalents of HCl yields, presumably again via an alkenylvinylidene complex, a five-coordinate alkenyl(dichloro) complex with a trigonal-bipyramidal coordination geometry (Scheme 3.29) [3]. 

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