Cerium III Compounds

Pour 1 ml of cerium nitrate into a test tube and add a few drops of sodium hydroxide. What happens Write the equation of the reaction. Act on the precipitate with an excess amount of the sodium hydroxide. Does cerium hydroxide react with sodium hydroxide  

React the cerium hydroxide precipitate with 1 N solutions of hydrochloric, sulphuric, and nitric acids. Write the equations of the reactions. 

Prepare cerium(III) hydroxide as described above and let it stand in the air. In a few hours, note what changes occurred in the precipitate. Write the equation of the reaction. 

Add a hydrogen peroxide solution to a cerium(III) hydroxide precipitate. How does the colour of the precipitate change Write the equation of the reaction. 

Add a sodium carbonate solution to a cerium nitrate one. What do you observe Write the equation of the reaction. How do mineral acids react with the obtained salt  

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Hydrated sulfato complexes of the type M M (S04)z JtH20 (Table 4) are known for M = U and Pu, and (NH4)2U2(S04)4-9H20 may be of the same type. KPu(S04)2-H20 and the corresponding dihydrate are isostructural with the neodymium(III) analogues and NH4Pu(S04)2 4H20 is isomorphous with the corresponding cerium(III) compound. Salts of other complex anions, such as KjM (S04)4 (M = Np, Pu), are also known. 

The 4f" - 4f" 5d transition occurs in the near-ultraviolet for cerium(III) praseodymium(III) and terbium(III). These transitions tend to be broad and the upper 5d level is split by the ligand field surrounding the ion. Ryan and Jprgensen (1966) have prepared the RCU , and RBrl ions with the triphenyl-phosphonium cation and measured their spectra in an acetonitrile-succinonitrile mixed solvent. For the cerium(III) compounds the 4f" - 4f"" 5d transition... 

Cerous salts in general are colorless because Ce " has no absorption bands in the visible. Trivalent cerium, however, is one of the few lanthanide ions in which parity-allowed transitions between 4f and Sd configurations can take place and as a result Ce(III) compounds absorb in the ultraviolet region just outside the visible. 

Cerium(III) oxysulfide [12442-45-4], is a high melting stable compound that precipitates out when steel is treated with a cerium-based metal... 

Miscellaneous Compounds. Among simple ionic salts cerium(III) acetate [17829-82-2] as commercially prepared, has lV2 H2O, has a moderate (- 100 g/L) aqueous solubiUty that decreases with increased temperature, and is an attractive precursor to the oxide. Cerous sulfate [13454-94-9] can be made in a wide range of hydrated forms and has solubiUty behavior comparable to that of the acetate. Many double sulfates having alkaU metal and/or ammonium cations, and varying degrees of aqueous solubiUty are known. Cerium(III) phosphate [13454-71 -2] being equivalent to mona2ite, is very stable. 

Palladium (II) chloride and ferric (III) chloride were purchased from Sigma Chemicals Co. Cerium(III) nitrate from Pfaltz Bauer, Inc. y-Al203 (100 m2/g) from Alfa Chemicals ethanol (HPLC grade) and nitrobenzene (Certified ACS) from Fisher Scientific. Bis(triphenylphosphine)palladium(II) dichloride was generously donated by Dr. Ivan J.B. Lin (National Dong Hwa University, Taiwan). All compounds were used without further treatment. Carbon monoxide (99.0%) was obtained from Praxair. 

Marcantoni E, Nobili F, Bartoli G, Bosco M, Sambri L (1997) Cerium(III) chloride, a novel reagent for nonaqueous selective conversion of dioxolanes to carbonyl compounds. J Org Chem 62 4183 1184... 

V,/V-Bis(trifluoromethyl)hydroxylamine (5) is oxidized with potassium permanganate in acetic acid to an interesting free-radical compound, bis(trifluoromethyl)nitroxid-A7-yl(6), a pink-violet gas which condenses to a deep brown-violet liquid.246 Various oxidizing agents are effective in the oxidation of 5 to the corresponding nitroxyl 6.247 The best appears to be cerium(IV) salts either in the solid state or in aqueous acid solution.247 Efficient oxidation processes have been developed using aqueous potassium persulfate solutions, or electrochemical oxidation with cerium(III) nitrate and sodium nitrate in dilute nitric acid.247... 

Diphenylphosphine)lithium, 126 Nickel boride, 197 Samarium(II) iodide, 270 to 1,2-disubstituted compounds B-3-Pinanyl-9-borabicyclo-[3.3.1]nonane, 249 Titanium(III) chloride, 302 of phosphorus compounds Lithium aluminum hydride-Cerium(III) chloride, 159 of sulfoxides and sulfones Sodium iodide-Boron trifluoride ether-ate, 282... 

Tris(diethylamino)sulfonium difluoro-trimethylsilicate, 123 Tris(dimethylamino)sulfonium difluo-rotrimethylsilicate, 336 Tris(2-trimethylsilylethynyl)-cerium(III), 206 Vinyltrimethylsilane, 343 Silver Compounds... 

The oxidation detector for the fluorimetric analysis of carbohydrates in effluents from liquid chromatography columns provides a sensitive method of analysis in blood and urine [110]. The principle involves the reduction of cerium(IV) to cerium(III) by oxidizable compounds such as organic acids and many carbohydrates. The fluorescence... 

Oxo-4//-pyrido[l,2-a]pyrimidine-7-carboxylates 500 were obtained when 7-iodo-4T/-pyrido[ 1,2-a]pyrimidines 499 reacted with carbon monoxide in the presence of bis(triphenylphosphine)palladium(II) chloride catalyst and triethylamine (Scheme 29) (94MI2). From 7-iodo derivatives 499, 7-vinyl derivatives 501 and 7-(l-ethoxyvinyl) derivatives 502 were prepared with vinyltributyltin in the presence of Pd(PPh3)4 and with (1-ethoxy-vinyl)tributyltin in the presence of bis(triphenylphosphine)palladium(II) chloride catalyst, respectively, in toluene at 80°C. 7-(l-Ethoxy vinyl)pyr-ido[l, 2-a]pyrimidin-4-ones 502 were hydrolyzed to yield 7-acetyl derivatives 503. The acetyl group of compounds 503 was reduced with sodium borohydride in the presence of cerium(III) chloride in ethanol to give 7-(1 -hydroxyethyl)pyridopyrimidin-4-ones 504. 

Bacteria, antimicrobials against, 12, 456 Baeyer-Villiger oxidation, via tin amides, 9, 370 Barbier-Grignard-type reactions, and sonochemical metal insertions, 1, 315 Barbier-type reactions allenyl and propargyl tins, 9, 358 with allylic tins, 9, 357 with antimony(III) compounds, 9, 426 with bismuth(III) compounds, 9, 433 with cerium reagents, 10, 409 with indium compounds, 9, 685... 

Both complexes are readily oxidized to the corresponding ion(III) compounds by strong oxidants in acid solution. They can be successfully titrated with cerium(IV) sulfate in sulfuric acid.4 The equivalence point is best detected potentiometrically (Pt vs. calomel electrode). 

Acetyl- and 3-benzoylisoxazoles have been conveniently obtained by one-pot reactions of alkynes with ammonium cerium(IV) nitrate or ammonium cerium(III) nitrate tetrahydrate in acetone or acetophenone these processes probably involve 1,3-DC of nitrile oxides formed by nitration of the carbonyl compound by cerium salts <02TL7035>. 

Since all these materials have a certain solubility in the electrolyte, some contamination of the metal will occur. The Eltech Systems Corporation announced [246,247] a method to protect the substrate anode material by forming a Ce(IV) oxyfluoride layer on the anode. The protective layer is maintained by adding a Ce(III) compound to the electrolyte. However, cerium contaminates the aluminum metal so that it must be removed and recirculated to the electrolyte. 

CARBONYL ADDITIONS, CERIUM(III) CHLORIDE-PROMOTED, 76, 237 Carbonyl compounds, reactions with organolithiums or Grignard reagents, 76, 228 Carboxylic acid amides, 77, 27 Cells, storage of, 76, 80 Centrifugation, 76, 78... 

An example prepared by tin-lithium transmetallation is compound 637, which reacts with enolizable ketones, after transmetallation with cerium(III) chloride895. This intermediate was transformed into the corresponding vinylzinc reagent and, after palladium(O)-catalyzed cross-coupling reactions with aryl iodides, was used in the synthesis of the antitumor antibiotic rineomycinone B2 methyl ester940,941. The vinyllithium 627 has also been transformed into the corresponding vinyl iodide by stannylation followed by reaction with iodine. The arylation has been performed in this case by a palladium(0)-catalyzed... 

VII.21 CERIUM, Ce (Ar 140-12) - CERIUM(III) Cerium is a white-grey, soft metal, which melts at 795°C. In its compounds cerium can be tervalent and quadrivalent, forming cerium(III), Ce3+, and cerium(IV), Ce4+, ions respectively. 

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