Rhodium chloride 3-hydrate

Rhodium(lll) chloride hydrate Rhodium chloride, hydrate (8,9) (20765-98-4)... 

Synthesis. The most important starting material for rhodium compounds is rhodium(III) chloride hydrate [20765-98-4], RhCl3 nH2 O. Other commercially available starting materials useful for laboratory-scale synthesis include [Rh2(0000113)4] [5503-41 -3], [Rh(NH3)201]0l2 [13820-95-6], [Rh20l2(0O)4] [32408-34-7], and [Rh20l2(cod)2] [12092-47-6]. 

Catalyst A mixture of 5.26 g of rhodium chloride trihydrate, 0.34 g of palladium chloride, 18 g of carbon (Darco G-60), and 200 ml of water is rapidly stirred and heated to 80°. A solution of lithium hydroxide hydrate (2.7 g) in 10 ml of water is added in one portion and the heating discontinued. Stirring is continued overnight, after which the mixture is filtered and washed with 100 ml of 0.5 % aqueous acetic acid. The product is dried in a vacuum oven at 65°. About 20 g of the catalyst is thus obtained. 

Sodium rhodium chloride (Na RhCl is the hydrate form of rhodium that was... 

Hexammino-rhodium Chloride, [Rh(NHs)e]Cl3, may be obtained by heating chloro-pentammino-rhodium chloride in a closed vessel at 100° C. for some time, when, on addition of hydrochloric acid to the cooled mixture, the anhydrous salt is precipitated. It crystallises from hot concentrated hydrochloric acid in the anhydrous form, or, from hot dilute acid, with two molecules of water of hydration. The anhydrous salt crystallises in colourless rhombic plates or compact 1 Claus, J. p-akl. Ohem., 1854, 63, 99. 

The reduction of metal ions in higher oxidation states by CO and H20 has been known for many years. Work on the reduction of Hg2+, Ag+, Ni2+, Cu2 +, and Pd2+ has been summarized recently (4). The reduction of these metal ions does not proceed via a stable intermediate carbonyl. Since a metal carbonyl must be an intermediate in this reaction, however, the coordinated carbonyl must be very susceptible to attack by water, reacting as soon as it is formed. The ability of a metal in a higher oxidation state to activate a coordinated carbonyl to attack by as weak a nucleophile as water was noted previously in the description of the work by James et al., on the reduction of rhodium(III) by carbon monoxide and water (62). Here a stable rhodium(III) carbonyl, Rh(CO)Cl2-, can be observed as the initial product of reaction of RhCl3 3HzO with CO. The Rh(III) is then efficiently reduced to the rhodium(I) anion [RhCl2(CO)2], even in nonaqueous solvents such as dimethylacetamide, where the only water available for reaction is the water of hydration of the starting rhodium chloride. 

Reaction (166) is also catalyzed by acidic rhodium chloride solutions under similar conditions to those used for ruthenium. Aquachloro complexes were again implicated and the most active species was [RhCl5(H20)]3. The hydration step was thought to involve a four-centred transition state (134).616 Here also, inhibition at low and high chloride ion concentration occurred. 

Methods for the preparation of tris(ethylenediamine)rhodium-(III) chloride hydrate and for its resolution by means of the diastereoisomer Ii (—)D-lRh(en)s] (- -)-tart 2 3H20 are presented. The resolution of tris(ethylenediamine)chromium(III) chloride by means of an analogous diastereoisomeric compound is also described. 

Interaction of the corresponding rhodium chloride with water and silver triflate gives the tris hydrate ... 

Rhodium(ll) acetate is obtained commercially (Degussa Corporation, Aldrich Chemical Company, Inc., AESAR/Johnson Matthey, or Johnson Matthey/Alfa Products) or prepared from rhodium(lll) chloride hydrate (Johnson Matthey) by the standard literature procedure.3... 

In a series of papers, Holah et al. studied the donor character of TPPO, TPPS, and TPPSe towards rhodium, ruthenium, and rhenium. Treatment of TPPO with rhodium(III) chloride hydrate in ethanol causes reduction to Rh(I) and gives the dimeric complex (XXVI) in which TPPO is j -bonded to the metal. 

Dichlorotetracarbonyldirhodium has been obtained by the action of carbon monoxide at high temperature and pressure on a mixture of anhydrous rhodium(III) chloride and finely divided copper powder and by reaction of rhodium(III) chloride 3-hydrate with carbon monoxide saturated with methanol at moderate temperatures and atmospheric pressure. The preparation described here is a modification of the latter method, without use of methanol. This procedure is considerably simpler than the recently described preparation which involves adsorption of rhodium chloride on silica gel, chlorination, and subsequent carbonylation. ... 

Double insertion of ethylene into aniline with the aid of rhodium(III) chloride hydrate gives the cyclization product, 2-methylquinoline (Eq. 3) [10]. Forcing reaction conditions and the use of an excess amount of aniline were required for this catalytic reaction. 

The chloride is obtainable also as a water-sol hydrate with variable amounts of water. Prepn of trihydrate Anderson, Basolo, Inorg. Syn. 7, 214 (1963). Similar to the chlorides of other platinum group metals, rhodium chloride readily forms double salts with alkali chlorides. 

SYNONYMS Synonyms vary depending upon the specific soluble rhodium compound, (hydrated rhodium trichloride) rhodium chloride, soluble rhodium trichloride. 

CHEMICAL PROPERTIES Chemical properties, reactivities, and incompatibilities vary depending upon the specific soluble rhodium compound, (hydrated rhodium chloride) rhodium chloride readily forms double salts with alkali chlorides some decomposition may occur at temperatures above 100°C (212°F) no incompatibilities have been reported FP (NA) LFL/UFL (NA) AT (NA) HC (NA). 

A. cis-DICHLOROBIS(l,2-ETHANEDIAMINE)RHODIUM(III) CHLORIDE HYDRATE, m-LRhfeiDiCliJCI HiO, AND tmns-DICHLOROBIS(l,2-ETHANEDIAMINE)RHODIUM(m) CHLORIDE HYDROCHLORIDE DIHYDRATE, tmns-[Rh(en)2CyCl HCI 2H2O... 

However, the hydrated rhodium (III) oxide mentioned on page 1588 dissolves readily in hydrochloric acid, giving a yellow solution. On evaporation of this solution, a residue of the hydrated chloride RhCla XH3O (x = 3-4) is left as a red deliquescent mass, which is called water-soluble rhodium chloride to distinguish it from the first product. Heating above 200°C converts this product to the water-insoluble RhCls. 

Endres and Maas prepared dimeric rhodium(II) carboxylate complexes 24a-24c from the sodium salts 25a-25c and rhodium(III) chloride hydrate in ethanol [Eq. (7)] [29, 30]. 

Little information is available on microemulsion-mediated synthesis of rhodium particles. Considering the importance of Rh nanoparticles in catalytic reactions, Kishida et al [426] developed a method using microemulsions. The reverse micelle was prepared with the surfactant NP-5 and cyclohexane as the continuous phase. An aqueous solution of rhodium chloride was solubilized in the micelle and hydrazine directly added to it at 25°C. The average particle size of rhodium thus obtained was about 3 nm. Kishida et al. [427] later extended the method to the use of a variety of non-ionic and ionic surfactants (C-15, i.e. polyoxyethylene(15)cetyl ether, L-23, i.e. polyoxyethylene(23)lauryl ether, NP-5 and NaAOT), as also cyclohexane or 1-hexanol (according to necessity) as the continuous phase. The reactants remained the same, i.e. rhodium chloride and hydrazine hydrate. In addition, the rhodium particles thus synthesized were coated with silica via hydrolysis-polycondensation of tetraethyl orthosilicate. The size of Rh varied in the range 1.5-4.0 nm in a typical case, a 4 nm particle was covered with a 14 nm thick layer of silica. 

The metal precursor silver nitrate (Reanal, purity 99.9%), palla-dium(II) chloride, rhodium(III) chloride hydrate (purity 98 /o), and the reducing agent sodium borohydride (purity 99%) were obtained from Aldrich. A polymer was used to stabilize the Pd and Rh nanoparticles poly(A-vinyl-2-pyrrolidone) (PVP, K-30, average molecular weight 4x10" g, Fluka). 

Cl2HsoCl6CoCrNi20s, (+) Tris(ethylenediamine)cobalt(III) (-) tris-(ethylenediamine)chromium(III) chloride hydrate, 42B, 729 Cl2H6oCl6CrNi20gRh, (+) Tris(ethylenediamine)chromium(III) (+)-tris-(ethylenediamine)rhodium(III) chloride hydrate, 42B, 729 Cl2H60CI7CO2N12NaOg, Sodium D-tris(ethylenediamine)cobalt(III) chloride hexahydrate, 19, 539 21, 547 Cl2H60CI7CO2N12NaOfi, Sodium L-tris-(ethylenediamine)cobalt(111) chloride hexahydrate, 19, 539... 

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