Azoxy

The alkaline reduction of an aromatic nitro-compound to give the azoxy... 

The fact that a mixed azoxy-compound, such as p toluencrazoxy-benzene, CH3CgH4NO NCgH5, exists in two isomeric forms, disproves the earlier symmetric formula (A) alloted to azoxybenzene, and C H N C H N >0 confirms the formula (B), in which... 

It must be noted, however, that nitroso, azoxy and azo compounds when subjected to the same treatment yield res])ectively hydroxylamines, hydrazo and hydrazine compounds, all of which reduce ammoniacal silver nitrate solution in the cold. 

They are always coloured but give colourless products upon reduction. Hydrazo and azoxy compounds are reduced in acid solution to the parent amine. 

Azoxy Compounds. Where the position of the azoxy oxygen atom is unknown or immaterial, the compound is named in accordance with azo rules, with the affix azo replaced by azoxy. When the position of the azoxy oxygen atom in an unsymmetrical compound is designated, a prefix NNO- or ONN- is used. When both the groups attached to the azoxy radical are cited in the name of the compound, the prefix NNO- specifies that the second of these two groups is attached directly... 

Azosprillum Azo-stilbene dyes Azotobacter Azotobacter agilis Azotobacter paspali Azoxy... 

In catalytic hydrogenation, a compound is reduced with molecular hydrogen in the presence of a catalyst. This reaction has found appHcations in many areas of chemistry including the preparation of amines. Nitro, nitroso, hydroxylamino, azoxy, azo, and hydrazo compounds can all be reduced to amines by catalytic hydrogenation under the right conditions. Nitriles, amides, thioamides, and oximes can also be hydrogenated to give amines (1). Some examples of these reactions foUow ... 

Alkoxyl tion. The nucleophilic replacement of an aromatic halogen atom by an alkoxy group is an important process, especially for production of methoxy-containing iatermediates. Alkoxylation is preferred to alkylation of the phenol wherever possible, and typically iavolves the iateraction of a chloro compound, activated by a nitro group, with the appropriate alcohol ia the presence of alkaU. Careful control of alkaU concentration and temperature are essential, and formation of by-product azoxy compounds is avoided by passiag air through the reaction mixture (21). 

Methyl-onn-azoxymethyl acetate (Methyl azoxy methyl acetate)... 

Controlled reductions arc also possible with a variety of other reagents m-Trrfluoromethylnitrobenzene is converted to the azoxy derivative with hot potassium hydroxide-methanol [SS] but gives the arrune with hot sodium sulfide-sodium hydroxide solution [iS9] (equation 71)... 

Nitro-compounds yield a series of reduction products accordmgto the nature of the reducing agent. Alkaline reducing agents sodium methylate, zinc dust and caustic soda, stannous chloride and caustic soda, produce azoxy, azo- and hydiazo-compounds. 

Azo- and Azoxy-compoiinds. Both classes of compounds ore usually highly coloured and are rapidly decolorised by v3rming with a solution of stannous chloride and hydrochloric acid, forming amino-cotnpounds (see Reactions, pp. i73i i77J-... 

The synthesis of the azoxy compounds has seen significant progress in the past decade. As already noted, compounds of this type may be prepared by... 

Only a single example of azofuroxan oxidation to an azoxy derivative is known (99MC15). The most successful way to azoxyfuroxanes is reductive coupling of 4-nitrofuroxans with zinc dust in aqueous acetic acid (Scheme 151). 3-Nitrofuroxans do not form the expected 3,3 -azoxy derivatives the starting compounds decompose under similar conditions (99MC15). 

Isomeric azoxy derivatives 227 and 228 have been prepared by condensation of the corresponding amino and nitroso substrates (Scheme 155) (88UP1). 

---