Rhodium soluble compounds

RHODIUM (soluble compounds, as Rh)(Soluble rhodium compounds have variable molecular formulas and variable formula weights, depending upon the specific compound. The physical and chemical properties of one specific compound, for example, hydrate rhodium trichloride, are provided. The molecular formula for this substance is Cl3Rh-xH20. The molecular weight is reported as being greater than 209.)... 

Chick embryos exposed to rhodium on the eighth day of incubation were stunted mild reduction of limb size and feather growth inhibition were also observed. A number of rhodium compounds have tested positive in bacterial assays for genetic altering capability. The 2003 ACGIH threshold limit valuetime-weighted averages (TLV-TWAs) are 1.0 mg/m for the metal, l.Omg/m as Rh, insoluble compounds, and 0.01 mg/m as Rh, soluble compounds. 

This preparation is an illustration of the hydroformylation of olefins (oxo synthesis). The reaction occurs in the presence of soluble catalytic complexes containing metals of Group VIII of the periodic system. Although the metal originally used by Roelen and still largely used in the industry for the production of aliphatic aldehydes and alcohols is cobalt, the most active and selective catalysts are rhodium-containing compounds. The catalytic activity of the other Group VIII metals is in... 

In 2 M HCl medium rhodium forms anionic complexes with SnC and Cl ions. With a large excess of tin(II), and at room temperature, a stable red complex is obtained after 1 h. The same effect is reached with 10-15 min heating on a boiling water-bath. The complex gives with Rhodamine 6G (R6G) (formula 4.30) a sparingly soluble compound that collects on the inside surface of the separating funnel after shaking (for 45 s) of an aqueous phase with DIPE. 

In the first stage, 1-butene is preferentially converted to valeraldehyde. This takes place in a low-pressure process, in which the catalyst used is a rhodium complex compound containing water-soluble phosphines as ligands. A solubilizer is also added. In the second stage, the 2-butene not converted in the first stage is hydroformylated with a cobalt catalyst. Part of the valeraldehyde obtained is then hydrogenated to amyl alcohol [109]-[111]. 

RHODIUM, SOLUBLE SALTS (AS Rh) Rh Synonyms vary depending upon spKiPic compound None hazardous Properties vary depending upon specifk compound ... 

Rhodium complexes with oxygen ligands, not nearly as numerous as those with amine and phosphine complexes, do, however, exist. A variety of compounds are known, iucluding [Rh(ox)3] [18307-26-1], [Rh(acac)3] [14284-92-5], the hexaaqua ion [Rh(OH2)3] [16920-31 -3], and Schiff base complexes. Soluble rhodium sulfate, Rh2(804 )3-a H2 0, exists iu a yellow form [15274-75-6], which probably coutaius [Rh(H20)3], and a red form [15274-78-9], which contains coordinated sulfate (125). The stmcture of the soluble nitrate [Rh(N03)3 2H20 [10139-58-9] is also complex (126). Another... 

The use of dirhodium(II) catalysts for catalytic reactions with diazo compounds was initiated by Ph. Teyssie [14] in the 1970s and rapidly spread to other laboratories [1]. The first uses were with dirhodium(II) tetraacetate and the more soluble tetraoctanoate, Rh2(oct)4 [15]. Rhodium acetate, revealed to have the paddle wheel structure and exist with a Rh-Rh single bond [16], was conve-... 

The ketone hydrosilylation shown in Fig. 7 was used as a test reaction. This can be catalyzed by the fluorous rhodium complexes 16-Rf6 and 16-Rfs under fluorous/organic liquid/liquid biphase conditions [55,56]. These red-orange compounds have very httle or no solubihty in organic solvents at room temperature [57]. However, their solubilities increase markedly with temperature. Several features render this catalyst system a particularly challenging test for recovery via precipitation. First, a variety of rest states are possible (e.g., various Rh(H)(SiR3) or Rh(OR )(SiR3) species), each with unique solubility properties. Second, the first cycle exhibits an induction period, indicating some fundamental alteration of the catalyst precursor. 

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