Argentic acid

The use of silver (II) salts, particularly argentic picolinate, as reagents for hydroxyl oxidation has also been disclosed recently. The reaction may be run in acid, neutral or basic media in aqueous or polar organic solvents at room or slightly elevated temperatures. Primary alcohols may be oxidized to aldehydes or acids depending on the conditions used. Amines and trivalent phosphorous compounds are more sensitive to oxidation with this reagent than are hydroxyl groups. 

Unlike Mn(VII) chromic acid oxidises hydrogen only in the presence of a catalyst, namely, argentous ion . The stoichiometry is... 

Trans fatty acids in liver of rats Silica AgNOj argentation 15... 

Argentation thin-layer chromatography is an extemely useful procedure for the separation of methyl esters of fatty acids. Saturated fatty acids have the highest Rf values, which decrease with the increasing degree of unsaturation, and for a particular acid, the trans isomer usually travels ahead of its corresponding cis isomer. The solvents most commonly used contain hexane and diethyl ether (9 1) although a mixture of 4 6 is used to separate compounds with more than two double bonds. In order to separate positional isomers of the same acid, conditions must be carefully controlled and multiple development in toluene at low temperatures is often necessary. 

Anthranilic acid, 278 Anthroquiixmes, 294 Antibiotics, 281 Antidiabetic drags, 264 Anlla liinp , Sfill Antipyrine, 297 Argentation, 68... 

With metallio oxides, hydrates, and some sidts it forms iodides. Even argeurio chloride is transformed by hydriodle acid into argentic iodide —... 

When passed through a solution of argentic nitrate, me tallic silver and nitric and phosphoric acids are formed —... 

Argentic chloride, bromide, and iodide are insoluble in water and nitrio acid. 

Strocchi and Holman (1971), with the aid of argentation TLC and GLC-mass spectrometry, identified the fatty acids in Tables 4.7 and 4.8. We have presented all of their data because the identifications were obtained by unequivocal methods, many previously tentative identifications were confirmed, and the results were quantitative. Strocchi and Holman did not identify the positional isomers of the unsaturates but found two or three peaks for most of the carbon numbers. Iverson (1983) determined the quantities of minor and trace fatty acids, verifying the findings of other investigators. 

Smith et al. (1978) have described a procedure for the GLC determination of cis and trans isomers of unsaturated fatty acids in butter after fractionation of the saturated, monoenoic, dienoic, and polyenoic fatty acid methyl esters by argentation TLC. Total trans acids were much higher, as measured by infrared spectrophotometry than by GLC, probably because some of the acids could have two or more of the trans bonds designated as isolated by infrared spectrophotometry. Enzymatic evaluation of methylene-interrupted cis, cis double bonds by lipoxidase resulted in lower values than those obtained by GLC. The authors mention that the lipoxidase method is difficult, requiring considerable skill, and suggest that their method is suitable for the determination of the principal fatty acids in complex food lipids such as bovine milk fat. 

Intramolecular electron transfer in a stepwise manner from the amine substrate to die silver(III) center in a 1 2 complex, [Ag(OH)4] -iV,/V-dimcthylanilinc, has been observed.44 The kinetics of oxidation of some aliphatic, heterocyclic, and aromatic aldehydes towards bis(dihydrogentellurato)cuprate(III) and argentate(III) in alkaline medium have been studied.45 A negative salt effect was observed in the oxidation of aminoacetic acid by diperiodatocuprate(III) complex in alkaline medium.46 The oxidation of glutamic acid by thallium(III) perchlorate is catalysed by Ru(M), Os(III), and Nd(III) in a free radical mechanism and the rate is inversely dependent on [H+] concentration.47... 

Silver nitrate Lunar caustic fused silver nitrate molded silver nitrate argent nitras nitric acid silver (I) salt nitric acid silver (1+) salt Silver (1+) ni trate No data AgN03... 

Reaction of shea triterpene alcohols with acetic anhydride and sulphuric acid to produce coloured products (Fitelson s reaction) was the basis of a sensitive early test for the presence of shea butter in cocoa butter (Fincke, 1975). Analysis of the triterpene fraction of a commercial cocoa butter by TLC fractionation followed by GC (Fincke, 1976), or argentation TLC followed by GC (Gegiou and Staphylakis, 1985), have been shown to have potential for detecting CBEs in chocolate based on the difference in levels of P-amyrin, butyrospermol and... 

The quantitative determination of individual isomers of tram-18 1 fatty acids in milk fat is not straightforward. It involves a multi-stage analytical procedure (i.e., transesterification of milk fat, argentation TLC of the fatty acid esters to separate the civ-isomers and tram-isomers, followed by capillary GC). This method gives an almost complete separation of the 13 individual tram-18 1 isomers, from A4 to A16 (Precht and Molkentin, 1996). 

SYNS LUNAR CAUSTIC NITRATE d ARGENT (FRENCH) NITRIC ACID, SILVER(1+) SALT SILBERNITRAT SILVER(1+) NITRATE SILVER NITRATE (DOT)... 

PROP Brownish-black, heavy, odorless powder. Light sensitive. D 7.22 25°/4°. Decomp at approx 200°. Yery sol in dilute nitric acid, ammonia less sol in NaOH solns insol in ale. IDLH 10 mg/m (as Ag). SYNS ARGENTOUS OXIDE DISILVER OXIDE... 

Argentic oxide, AgO, which is prepared by the electrolysis of silver nitrate in nitric acid [379], converts aromatic methyl homologues into aldehydes [380], primary alcohols into aldehydes [380] or acids [381], aldehydes into acids [382], primary amines into aldehydes and nitriles [381], and phosphines into phosphine oxides [38i]. 

Methyl homologues of aromatic compounds are oxidized to aldehydes by silver(II) oxide (argentic oxide) [380], by ceric ammonium nitrate [238, 417, 422], by selenium dioxide [513, 514, 5i5], by chromyl chloride [477, 667], by periodic acid [760], and by manganese dioxide [1127] (equation 169). 

Both aliphatic and aromatic alcohols, as well a s unsaturated alcohols, are oxidized in the liquid phase with argentic oxide in nitric or acetic acid at temperatures from -10 through 60 °C [5S6]. 

Aldehydes are also oxidized to carboxylic acids in high yields by argentic oxide at room temperature in aqueous tetrahydrofuran. However,... 

A somewhat similar oxidation takes place when an aldehyde is treated with sodium cyanide and manganese dioxide or argentic oxide [382], The reaction is assumed to proceed through a cyanohydrin, which is oxidized to an a-keto nitrile. The a-keto nitrile in turn is converted into an acid (by argentic oxide in methanol) or an ester (by manganese dioxide in methanol). The method is especially suited for a, -unsaturated aldehydes [382] (equation 354). 

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