Tris ruthenium chloride

A method for the electrochemical reduction of D-xylose to 2-deoxy-D-r/rr o-pentitol has been described. The homogeneous hydrogenation of sugars using tris-triphenylphosphine ruthenium chloride is improved in the presence of hydrogen chloride, which inhibits competitive decarbonylation of the sugar. L-(2,3)-Threitol is easily prepared from ( + )tartaric acid by lithium aluminium hydride reduction of the 2,3-0-isopropylidene derivative of diethyl tartrate, followed by acid hydrolysis of the resultant ketal. ... 

Chloro-2-(3-methyl-4H-1,2,4-triazol-4-yDbenzophenone (Oxidation of 7solution prepared by adding sodium periodate (2 g) to a stirred suspension of ruthenium dioxide (200 mg) in water (35 ml). The mixture became dark. Additional sodium periodate 18 g) was added during the next 15 minutes. The ice-bath was removed and the mixture was stirred for 45 minutes. Additional sodium periodate (4 g) was added and the mixture was stirred at ambient temperature for 18 hours and filtered. The solid was washed with acetone and the combined filtrate was concentrated in vacuo. The residue was suspended in water and extracted with methylene chloride. The extract was dried over anhydrous potassium carbonate and concentrated. The residue was chromatographed on silica... 

Meisel etal. [18-20] were the first to investigate how the addition of a polyelectrolyte affects photoinduced ET reactions. They found that charge separation was enhanced as a result of the retardation of the back ET when poly(vinyl sulfate) was added to an aqueous reaction system consisting of tris(2,2 -bipyridine)ruthenium(II) chloride (cationic photoactive chromophore) and neutral electron acceptors [21]. More recently, Sassoon and Rabani [22] observed that the addition of polybrene (a polycation) had a significant effect on separating the photoinduced ET products in an aqueous solution containing cir-dicyano-bis(2,2 -bipyridine)ruthenium(II) (photoactive donor) and potassium hexacyano-ferrate(III) (acceptor). These findings are ascribable to the electrostatic potential of the added polyelectrolytes. 

To a solution of 4-t-butylcyclohexanone (lmmol), tris(triphenylphos-phine)ruthenium(n) chloride (0.05 mmol) and silver trifluoroacetate (0.05 mmol) in toluene (5 ml) was added triethylsilane (1.5 mmol). The mixture was heated under reflux for 20 h, and concentrated under reduced pressure. The residue was diluted with hexane (3 ml), filtered and distilled to give a mixture of triethylsilyl ethers (0.96mmol, 96%), b.p. 70°CI 0.1 mmHg. G.l.c. analysis shows an axial (cis) equatorial (trans) ratio of 5 95—a result comparable to the best LAH results. 

Dienes such as 90 can be accessed by a multi-component reaction under ruthenium catalysis involving an allene 88 and an enone (methyl vinyl ketone in this case), with cerium(m) chloride as an additive in DMF (Scheme 26).95,96 With an allene concentration of 0.25 M, yields are moderate to good. Different ruthenium catalysts and additives were tested in order to optimize this reaction. CpRu(COD)Cl 89 and CpRu(MeCN)3PF6 appeared to be more versatile ones. The mono-, di-, tri-, and tetrasubstituted allenes have been investigated with methyl vinyl... 

Many catalysts, certainly those most widely used such as platinum, palladium, rhodium, ruthenium, nickel, Raney nickel, and catalysts for homogeneous hydrogenation such as tris(triphenylphosphine)rhodium chloride are now commercially available. Procedures for the preparation of catalysts are therefore described in detail only in the cases of the less common ones (p. 205). Guidelines for use and dosage of catalysts are given in Table 1. 

The formation of a ruthenium vinylidene is proposed as the key intermediate in the regioselective addition of hydrazine to terminal alkynes [55]. This reaction, which proceeds via addition of the primary amino group of a 1,1-disubstituted hydrazine followed by deamination, provides an unprecedented access to a variety of aromatic and aliphatic nitriles. The tris(pyrazolyl)borate complex RuCl(Tp)(PPh3)2 gave the best catalytic activity in the absence of any chloride abstractor (Scheme 10.17). 

The tris(ethylenediamine)ruthenium(III) species is obtained by oxidation of [Ru(en)3]2+ with, for example, iodine4 or bromine.6 The oxidizing agent and conditions employed must be chosen carefully to avoid further oxidation of the ethylenediamine ligand to coordinated diimine.7 In the present procedure solid silver anthranilate is used to oxidize [Ru(en)3] [ZnCl4], and [Ru(en)3] Cl3 is isolated. In this heterogeneous procedure the desired [Ru(en)3]Cl3 is the only soluble product and can easily be separated from the insoluble silver, silver chloride, and zinc dianthranilate. Other less soluble [Ru(en)3]3+ compounds can be obtained easily from the soluble chloride. 

We have tried to study the decomposition of ruthenium (I I) in aqueous media containing high concentrations of chloride, according to... 

C72H48CI2N6RU, Ruthenium(II), tris(4,7-diphe-nyl-l,10-phenantroline)-, chloride, 34 66 C72H8oCo4F24Ni2P4Rh4, Rhodium(III), dodeca-cyanotetrakis cyclopentadienylcobalt(III) tetrakis pentamethylcyclopentadienyl-, tetrakis hexafluorophosphate, 34 170 C72H96C09M05N48O24 xMeOH XH2O,... 

CI2N6RUC72H48, Ruthenium(II), tris(4,7-diphenyl-1,10-phenantroline)-, chloride,... 

Grignard reagents, 138 Methyl acrylate, 183 Palladium catalysts, 230 Ruthenium(III) chloride, 268 Other methods l-Acetoxy-2,4-hexadiene, 2 Palladium catalysts, 230 Tri-p-carbonylhexacarbonyldiiron, 320... 

Anhydrous ruthenium(lll) chloride, RuCL, is made by direct chlorination of the metal at 700°C. Two aliotropic forms result. The trihydrate is made by evaporating an HQ solution of rulheinuiu(III) hydroxide to dryness or reducing ruthenium(VIII) oxide in a HQ solution. The tnhydrate, RuCk 3R>0, is the usual commercial form. Aqueous solutions of the tri-hydrate are a straw color in dilute solution and red-brown in concentrated solution. Ruthenium(lll) chloride in solution apparently forms a variety of aquo- and hydroxy complexes. The analogous bromide. RuBr3, is made by the same solution techniques as the chloride, using HBr instead of HQ. 

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