Amine oxides salt formation

Primary and secondary amines, double bonds, aldehydes, sulfides and certain aromatic and dihydroaroraatic systems are also oxidized by chromium VI reagents under standard hydroxyl oxidizing conditions. Amines are commonly protected by salt formation or by conversion to amides. Aldehydes and... 

Suitable catalysts are copper(I) salts [e.g., Cu(I) chloride, bromide, and sulfate] in combination with amines to form oxidation sensitive phenolates. The amine/copper salt ratio must be made as large as possible, to minimize the formation of diphenylquinone and to give a high molecular weight. 

Pigment Blue 1 [1325-87-7] 42595 2 triarylcarbonium PTMA salt (Victoria Blue B) condensation of 4,4 -bis-IV,IV-dimethyl aminobenzophenone with N-ethyl-l-naphthyl amine, followed by oxidation and salt formation... 

If the L is poor as in amides, Lewis salt formation allows an aluminum oxide to be kicked out instead of the amine (path AdN, then An, followed by the Lewis salt serving as a hydride source, then Ep, and then AdN). 

The best known of these is the ozonation of tertiary amines to amine oxides (II) (i). Henbest and Stratford (11) and Shulman (17) have shown that competing with this is an ozone attack on the alpha position of an alkyl side chain to produce various decomposition products of III. Henbest (11) showed that amine oxide formation is favored in chloroform and methanol, while side chain oxidation is predominant in hydrocarbon solvents. Also of considerable interest are the reported conversions, during ozonation, of phenylenediamines to Wursters salts (VII) (8, 14), of liquid ammonia to ammonium ozonate (VA) at a low temperature 18), and of amines to amine hydrochlorides (VB) in chlorinated hydrocarbon solvents 17, 19), Finally, an early report states that azobenzene and quinone are obtained upon ozonation of aniline (15). 

Commercial amine oxide contains some amount of unoxidised tertiary amine that may account for some of the cationic behaviour of the product, particularly at low pH. The formation of semipolar N-0 bonds both rises affinity to water and highly reduces the basic character of the amine so that the transition into a salt becomes possible at low pH only or as a result of mixed micelle formation with an anionic surfactant at neutral pH [49, 50] ... 

Because of the relatively easy oxidation of mercury, anodic waves are observed with the DME only for the strongest reducing agents such as hydroquinones, enediols (e.g., ascorbic acid), phenylhydroxylamine derivatives, and certain aldehydes. Numerous organic substances nevertheless yield anodic waves corresponding to mercury-salt formation, e.g., thiols and other derivatives of bivalent sulfur, amines, and some... 

Formation of allylic amines 93 and enamines 94 is expected by oxidative amination of alkenes via aminopalladation and jS-H elimination using Pd(II) salts. Formation of allylic amines is favored. 

Aryl halides are frequently prepared from the corresponding aryldiazonium salts by diazotation procedures. However, diazonium salts can be subjected directly to very mild Heck arylation conditions, which deliver coupled products (entry 19). Preferably, the reaction is executed in nonaqueous solvents such as acetonitrile, acetone, or methylene chloride with sodium acetate as base and with palladiumbis(dibenzylideneacetone) as catalyst. Alternatively, a combination of the amine and f-butyl nitrite, in a mixture of acetic acid and monochloroacetic acid, can provide the desired product directly, which makes the isolation of a diazonium salt unnecessary (entry 20). " It is also possible to use aromatic acid anhydrides as oxidative addition precursors (entry 21). Clearly, anhydrides are very interesting starting materials for a number of Heck reactions due to price and absence of halide salt formation. 

Highly ethoxylated amines and diamines have been recommended for demulsification of crude oil. Combinations of quaternary ammonium salts and amines oxides are useful for foaming and silt suspension. Coco alkyltrimethylammonium chloride and bis(2-hydroxy-ethyljcoco alkylamine oxide comprise the preferred combinations. Quaternary ammonium salts, including coco alkyltrimethylammonium chloride, are useful for preparing foamed oil-in-water emulsions, which can dissolve paraffins and asphaltenes without formation damage. The pyrolized amine salts of humic acid have been used in filtrate control additives. 

Dissolve 0.1 g of an amine in 2 mL of water to which 8 drops of concentrated sulfuric acid have been added. Use a large test tube. Often, a considerable amount of solid forms in the reaction of an amine with sulfuric acid. This solid is likely to be the amine sulfate salt. Add about 4 mL of water to help dissolve the salt. Any remaining solid will not interfere with the results of this test. Cool the solution to 5°C or less in an ice bath. Also cool 2 mL of 10% aqueous sodium nitrite in another test tube. In a third test tube, prepare a solution of 0.1 g j8-naphthol in 2 mL of aqueous 10% sodium hydroxide, and place it in an ice bath to cool. Add the cold sodium nitrite solution, drop by drop while shaking, to the cooled solution of the amine. Look for bubbles of nitrogen gas. Be careful not to confuse the evolution of the colorless nitrogen gas with an evolution of brown nitrogen oxide gas. Substantial evolution of gas at 5°C or below indicates a primary aliphatic amine, RNH2. The formation of a yellow oil or a yellow solid usually indicates a secondary amine, RjNH. Either tertiary amines do not react, or they behave like secondary amines. 

These results pointed ont that quantitative gas-solid reactions with aliphatic amines (salt formation) must be carried out with powdered 2-mercaptobenzothiazole for obtaining reactive crystal faces. Also, solid-solid oxidation with l-oxo-2,2,6,6-tetramethyl-piperidinium nitrate required milling for breaking the self-protection. ... 

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