Ruthenium, conversion to trichloride

In some instances, particularly when the ruthenium trichloride sample contains more than the usual amount of water (this may occur, e.g., with old samples or on long exposure to moist air), the isolated product may be a mixture of Ru3(CO)12 and Ru4(/ -H)4(CO)12 (as indicated by the IR v(CO) spectrum). In such cases, depending upon the final product required (a) the product may be used directly as in the synthesis of Ru4( -H)4(CO)12 described below, when conversion to the cluster carbonyl hydride is completed by reaction with H2 or (b) treatment of the product with CO for 1 h while suspended in refluxing octane, using the apparatus depicted in Fig. 1, results in conversion of any Ru4(/i-H)4(CO)12 to Ru3(CO)12. 

Sodium hypochlorite is used for the epoxidation of double bonds [659, 691] for the oxidation of primary alcohols to aldehydes [692], of secondary alcohols to ketones [693], and of primary amines to carbonyl compounds [692] for the conversion of benzylic halides into acids or ketones [690] for the oxidation of aromatic rings to quinones [694] and of sulfides to sulfones [695] and, especially, for the degradation of methyl ketones to carboxylic acids with one less carbon atom [655, 696, 697, 695, 699] and of a-amino acids to aldehydes with one less carbon [700]. Sodium hypochlorite is also used for the reoxidation of low-valence ruthenium compounds to ruthenium tetroxide in oxidations by ruthenium trichloride [701]. 

Aldehydes can be oxidized by nickel [91] and ruthenium oxides. Whereas mthenium tetroxide [92] gives poor conversions to the corresponding acids, catalytic amounts of ruthenate [93] in the presence of a secondary oxidant, such as NaBrOs or K2S20g, give better yields. Other ruthenium species for the catalytic oxidation of aldehydes to carboxylic acids are tris(triphenylphosphine) ruthenium dichloride [94] in the presence of hypervalent iodine [95] and ruthenium trichloride [96] in combination with periodate [81]. 

Palladium. The dependence of catalytic activity on the composition of the palladium(ii) complexes [Pd(NH3) (OH2)4 ] + for hydration of acetylene has been assessed the most active catalyst has n = 1. Palladium(ii) sulphate catalysis of the hydration of acetylene has been described. The conversion of vinyl chloride to acetal involves addition of alcohol rather than water. It is catalysed by palladium(ii) chloride, as well as by ruthenium trichloride or rhodium trichloride. ... 

Another alkene cleavage method is illustrated by the conversion of the alcohol moiety in 5.228 (the template) to a mesylate and then to azide 5.229. Oxidative cleavage with periodate and ruthenium trichloride was followed by hydrogenation of the azide to give 3-amino-2-methylpentanoic acid, 5.230. 

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