Oxidation silver dichromate

In neutral solution, the indicator is potassium chromate(VI). In acid solution the CrOj ion changes to Cr202 (p. 378), and since silver dichromate(VI) is soluble, chromate(VI) is not a suitable indicator other methods can be used under these conditions. (In alkaline solution, silverfl) oxide precipitates, so silver(I) nitrate cannot be used under these conditions.)... 

Diazirines have been prepared by dehydrogenation of diaziri-dines with mercuric oxide, silver oxide, or dichromate-sulfuric acid. The present procedure corresponds to that of Schmitz and Ohme. The procedure for the preparation of the 3,3-penta-methylenediaziridine has been reported by H. J. Abendroth. ... 

Several other polymer-bound oxidizing reagents have recently been reported in the literature (reaction 14). A polyethyleneimine-supported silver dichromate 35 has been shown to be a stable, mild, and efficient oxidizing agent for the conversion of alcohols to carbonyl compounds.51 A... 

Potassium superoxide. Pyridinium chlorochromate. Pyridinium dichromate. Pyridinium fluorochromate. Silver(I) oxide. Silver(II) oxide. Sodium chlorite. Sodium hypochlorite. Sodium periodate. Sodium peroxide. Thallium(in) trifluoroacetate. Trifluoroperacetic acid. 

Many chromium oxidants suffer from problems of stability, light sensitivity or acidity, but tetrakis(py-ridine)silver dichromate is stable, nonphotosensitive, nonhygroscopic and a neutral oxidant It can be used to oxidize allylic and benzylic alcohols selectively in benzene. Unfortunately, it cannot be used in chlorinated solvents because it decomposes in these solvents. 

Silver dichromate-pyridine complex (tetrapyridine silver dichromate), Ag2Cr207 4C5H5N, an orange-yellow solid prepared by adding a warm solution of potassium dichromate to a solution of silver nitrate in water and pyridine, oxidizes allylic and benzylic alcohols to aldehydes and acyl-tiins to a-diketones [659]. 

Oxidations with a complex of pyridine with silver dichromate in benzene do not offer any advantages, and refluxing is necessary [659]. 

Silver iododibenzoate. Silver oxide. Sodium dichromate. Sodium persulfate. Thal-lium(III) trifluoroacetate. Trimethylamine oxide. Vanadium oxyacetylacetonate. 

A silver dichromate complex with poly(ethyleneimine) has been used to oxidize benzyl alcohol in toluene to ben-zaldehyde in 98% yield.199 The polymeric reagent could be regenerated several times with no loss in activity. No... 

Silver(I) bromide Silver(I) carbonate Silver(I) chloride Silver(I) chromate Silver(I) cyanide Silver(I) fluoride Silver(I) iodide Silver(I) nitrate Silver(I) nitrite Silver(I) oxide Silver(I) phosphate Silver(I) sulfate Silver(I) thiocyanate Silver(II) oxide Sodium Sodium acetate Sodium bromate Sodium bromide Sodium carbonate Sodium chlorate Sodium chloride Sodium dichromate Sodium fluoride Sodium hydrogen phosphate Sodium hydroxide (aq) Sodium iodate Sodium iodide Sodium nitote Sodium nihite Sodium oxide Sodium peroxide Sodium sulfate Sodium sulfate decahydrate Sodium sulfide Sodium teh aborate Strontiimi Sh ontiimi bromide Sh ontiimi bromide hexahych ate Sh ontiimi carbonate Sh ontiimi chlorate Sh ontiimi chloride Sh ontiimi chloride hexahych ate Sh ontiimi chromate Sh ontiimi fluoride Sh ontiimi hydroxide Sh ontiimi iodate Sh ontiimi iodide Sh ontiimi nitote... 

Chromium oxide (Cr203). Up to 0.1% colorimetrically with diphenylcarbizide at 540 nm. Above 0.1% but as a minor constituent, colorimetrically with EDTA at 550 nm. As a major constituent by oxidation to dichromate by peroxodisulfuric acid using a silver nitrate catalyst, destruction of permanganate with HCl and titration against ferrous ammonium sulfate using diphenylamine-4-sulfonate indicator. 

Potassium hydrogenphthalate Potassium hydrogenbiiodate Silver nitrate Sodium oxalate Arsenic(lll) oxide Potassium dichromate Ammonium hexanitrocerate(IV) Potassium iodate Potassium bromide Calcium carbonate Zinc oxide Ni, Zn, Cu metals Anhydrous disodium EDTA... 

Bromine(III) fluoride fluorinates everything which dissolves in it. Numerous oxides, halides and salts of oxyacids are converted into fluorides. Carbonates, nitrates and iodates are usually completely converted into the fluorides, while some of the metal oxides, such as BeO, MgO, ZnO or AI2O3 are only partly fluorinated by liquid bromine(III) fluoride. Sodium vanadate yields a mixture of tetrafluorooxovanadate and hexafluorovanadate i, potassium or silver dichromates give KCrOF4 and AgCrOF4 resp. i. Potassium permanganate is converted into KMnFs, potassium metaphosphate into potassium hexafluoro-phosphate and sodium borate into the tetrafluoroborate ... 

Related Reagents. A/-Chlorosuccinimide-Dimethyl Sulfide Chromic Acid Dimethyl Sulfide-Chlorine Dimethyl Sulfoxide-Acetic Anhydride Dimethyl Sulfoxide-Dicyclo-hexylcarbodiimide Dimethyl Sulfoxide-Oxalyl Chloride Dimethyl Sulfoxide-Phosphorus Pentoxide Dimethyl Sulfoxide-Sulfur Trioxide/Pyridine Dimethyl Sulfoxide-Trifluoroacetic Anhydride Dimethyl Sulfoxide-Triphosgene Manganese Dioxide Pyridinium Chlorochromate Pyridinium Dichromate Ruthenium(rV) Oxide Silver(I) Carbonate on Celite 1,1,1-Triacetoxy-1,1-dihydro-1,2-benziodoxol-3( 1 H)-ons. 

Common features of the tetrakis(pyridine)silver dichromate oxidations of vicinal and non-vicinal diols and their monoethers, aliphatic aldehydes, a-hydroxy acids (glycolic, lactic, malic and few substituted mandelic acids), and aliphatic primary alcohols in DMSO are = a + h[H+], fractional order in the substrates, = 5.91 (ethane diol), 5.80 (MeCHO), 5.78 (mandelic acid), and 5.85 (ethanol). The solvent effects have been analysed using Taft and Swain multiparametric equations for all the substrates except mandelic acid, for which the Kamlet and Swain multiparametric equation is used. The rate constants for aldehydes correlated with Taft s a values with a negative reaction constant. The rate-determining step for oxidation of aldehydes and hydroxy acids is the transfer of H ion. For diol oxidation, the... 

The chromates of the alkali metals and of magnesium and calcium are soluble in water the other chromates are insoluble. The chromate ion is yellow, but some insoluble chromates are red (for example silver chromate, Ag2Cr04). Chromates are often isomorph-ous with sulphates, which suggests that the chromate ion, CrO has a tetrahedral structure similar to that of the sulphate ion, SO4 Chromates may be prepared by oxidising chromium(III) salts the oxidation can be carried out by fusion with sodium peroxide, or by adding sodium peroxide to a solution of the chromium(IIl) salt. The use of sodium peroxide ensures an alkaline solution otherwise, under acid conditions, the chromate ion is converted into the orange-coloured dichromate ion ... 

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