Silver II Oxide

Silver(II) Oxide. Silver(II) oxide (AgO) is the most powerful of the three oxidants presented in this section. Although it is not widely used, Ag(II) oxide converts aldehydes and alcohols to carboxylic acids 

Submitted by Robert N. Hammer and Jacob Kleinberg Checked by Henry F. Holtzclaw, JR.,t and K. W. R. Johnsont 

Silver (II) oxide has been made by the hydrolytic action of boiling water on a substance of the approximate formula Ag708N03, a material which is obtained by the electrolytic oxidation of silver(I) nitrate solutions.1-4 A more rapid and convenient process for the preparation of this oxide involves the oxidation of silver (I) nitrate by means of potassium peroxydisulfate in an alkaline medium.5,6 

Seventy-two grams of sodium hydroxide (1.8 mols) in pellet form is added portionwise, with constant stirring, to 1 1. of water, which is maintained at approximately 85°. Seventy-five grams of potassium peroxydisulfate (0.28 mol) in the form of an aqueous slurry is added to the hot alkaline solution this is followed by the addition of 51 g. of silver(I) nitrate (0.30 mol) dissolved in a minimum amount of water. The temperature of the resulting mixture is raised to 90°, and stirring is continued for approximately 15 minutes. 

The precipitate of black silver(II) oxide is filtered on a large Buchner funnel, and sulfate ion is removed by washing with water which has been made slightly alkaline with sodium hydroxide. The product is air-dried. Yield, 35 g. (94%). Anal. Calcd. for AgO Ag, 87.08. Found Ag, 

90 (by gravimetric chloride method, after dissolution of the product in 3 N nitric acid). 

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The conversion of primary alcohols and aldehydes into carboxylic acids is generally possible with all strong oxidants. Silver(II) oxide in THF/water is particularly useful as a neutral oxidant (E.J. Corey, 1968 A). The direct conversion of primary alcohols into carboxylic esters is achieved with MnOj in the presence of hydrogen cyanide and alcohols (E.J. Corey, 1968 A,D). The remarkably smooth oxidation of ethers to esters by ruthenium tetroxide has been employed quite often (D.G. Lee, 1973). Dibutyl ether affords butyl butanoate, and tetra-hydrofuran yields butyrolactone almost quantitatively. More complex educts also give acceptable yields (M.E. Wolff, 1963). 

The dimethyl ethers of hydroquiaones and 1,4-naphthalenediols can be oxidized with silver(II) oxide or ceric ammonium nitrate. Aqueous sodium hypochlorite under phase-transfer conditions has also produced efficient conversion of catechols and hydroquiaones to 1,2- and 1,4-benzoquiaones (116), eg, 4-/-butyl-l,2-ben2oquinone [1129-21-1] ia 92% yield. 

Silver (II) oxide [1301-96-8] M 123.9, m >100 (dec), d 7.22. Soluble in 40,000 parts of H2O, and should be protected from light. Stir with an alkaline solution of potassium peroxysulfate (K2S2O8) at 85-... 

Anhydrous AgF is best made by fluorination of finely divided silver at room temperature alternatively it can be made by dissolving silver(II) oxide in hydrofluoric acid and crystallizing ... 

The decomposition of silver(II) oxide in vacuum at 356—407 K exhibits a sigmoid a—time curve in which the deceleratory period predominates... 

Among other oxidizing agents that have been used to accomplish the conversion of ArCHs to ArCHO are ceric ammonium nitrate, ° ceric trifluoroa-cetate, and silver(II) oxide.Oxidation of ArCHa to carboxylic acids is considered at 19-11. 

The silver(II) oxidation of dithionate " is of interest because this reductant is rather inert and oxidation is often preceded by rate-determining disproportiona-... 

Hydrogen sulfide is rapidly oxidised, and may ignite in contact with a range of metal oxides, including barium peroxide, chromium trioxide, copper oxide, lead dioxide, manganese dioxide, nickel oxide, silver(I) oxide, silver(II) oxide, sodium peroxide, and thallium(III) oxide. In the presence of air, contact with mixtures of calcium oxide or barium oxide with mercury oxide or nickel oxide may cause vivid incandescence or explosion. 

SILVER II oxidation conditions —Current flow to cell... 

Silver(II) oxide is used to make silver oxide-zinc alkali batteries. Also, it is an oxidizing agent. 

Silver(II) Oxide. Add a soda solution and a potassium persulphate solution to 1 ml of a 0.1 N silver nitrate solution. What is the composition of the precipitate Write the equation of the reaction. What physical method can be used to distinguish silver(I) oxide from sil-ver(II) oxide ... 

A key step in a synthesis of the 6-deoxyanthracyclinone 4 involves, oxidation of 1 with silver(II) oxide to give the crude quinone a, which rearranges in the presence of a trace of IIC1 to the quinone 3 in high yield.1... 

Silver(II) oxide (AgO) dissolves in concentrated mineral acids to give Ag2+, with oxidizing power similar to S2Ojj plus Ag+. Excess Ag2+ can be removed by boiling ... 

In an effort to elucidate the mechanism of oxidative phosphorylation, 6-hydroxy-2,2,5-trimethyl-2H-naphtho[l,2-6]pyran (183) was treated with silver(II) oxide. The product (184) was a stable quinone hemiketal (71JOC4045). 

Silver(I) oxide, [CAS 20667-12-3]. AgjO. is made by action of oxygen under pressure on silver at 300°C, or by precipitation of a silver salt with carbonate-free alkali metal hydroxide it is covalent, each silver atom (in solid AgjO) having two collinear bonds and each oxygen atom four tetrahedral ones two such interpenetrating lattices constitute the structure. Silver(I) oxide is die normal oxide of silver. Silver(II) oxide, AgO, is formed when ozone reacts with silver, and thus was once considered to be a peroxide, Silvcr(III) oxide, Ag203, has been obtained in impure state by anodic oxidation of silver. 

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. 

Silver(I) acetate, 396 Silver hexafluoroantimonate, 467 Silver imidazolate, 467 Silver nitrite-Mercury(II) chloride, 467-468 Silver(l) oxide, 468-469 Silver(II) oxide, 469 Silver perchlorate, 469-470 Silver tetrafluoroborate, 471 Silver(I) trifluoracetate, 471 Simmons-Smith reagent, 210-211, 472, 598 Sinularene, 246 Slaframine, 114, 115 Sodium amalgam, 473-475 Sodium-Ammonia, 472 Sodium benzeneselenoate, 475 Sodium bicarbonate, 476 Sodium bis(methoxyethoxy)aluminum hydride, 93, 476-477 Sodium borate, 322 Sodium borohydride, 477-479, 499 Sodium borohydride-Cobalt(IF) chloride, 479 Sodium borohydride-Methanesulfonic acid,... 

Silver (II) oxide Argentic oxide silver peroxide silver suboxide di vsai1 No data AgO... 

TABLE 3-10. Physical and Chemical Properties of Silver (II) Oxide... 

Selenium dioxide, 4832 Silver oxide, 0032 Silver(II) oxide, 0025... 

The determination of n from measurement of peff is the most familiar application of magnetic susceptibility measurements to inorganic chemists. To the extent that the spin-only formula is valid, it is possible to obtain the oxidation state of the central atom in a complex. Thus an iron complex with a peff of 5.9B.M. certainly contains Fe(III) (high-spin d5) and not Fe(II). The diamagnetism of AgO rules out its formulation as silver(II) oxide, because Ag2+ has an odd number of electrons (d9) and should be paramagnetic it contains Ag(I) and Ag(III), in equal amounts. There are, however, a number of pitfalls, especially if reliance is placed on a single measurement at room temperature. The Curie law is rarely obeyed within the limits of experimental error. This means that the measured peff is somewhat temperature-dependent. A number of factors can be responsible for deviations from ideal Curie (or even Curie-Weiss) behaviour, and/or from the spin-only formula. 

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