Azo compounds amines

Enolate > amine > azo compounds > ring N > carboxylate > ether > carbonyl... 

Reductive alkylation has also been carried out on nitro, nitroso, azo, and other compounds that are reduced in situ to primary or secondary amines. Azo compounds react with aldehydes, in the presence of proline, and subsequent reduction with NaBH4 gives the chiral hydrazine derivative. ... 

TRICHLORO-2,2-DI(4-CHLORO-PHENYL)-ETHANE (50-29-3) Cj HjCls Combustible solid (flash point 324 to 340 F/162 to 171°C). Incompatible with strong oxidizers reducing agents, including metal hydrides, nitrides, sulfides, alkali metals, and metal alkyls ferric chloride aluminum chloride salts of iron or aluminum alkalis and alkaline media. May be inconqjatible with many alkali metals amines, azo compounds diazo compounds epoxides such as glycidol, nitrides. Reacts with aluminum and iron. On small fires, use water, foam, dry chemical or CO2 extinguishers. 

The further fate is not explicitly known, but molecule rearrangements and/or the addition of O2, NO c and NO3 is possible. From secondary amines, azo compounds or organic hydrazines (derived from hydrazine N2H4) can be given ... 

Azo-compounds can be obtained by reduction of nitro-compounds, or by oxidation of hydrazo-compounds. They are usually prepared, however, by reacting a phenol or amine with a diazonium salt. The coupling usually takes place in the position para to the hydroxyl or amino group, but if this position is occupied it goes to the ortho position, e.g. 

The azo-compounds are usually very stable, and can be directly chlorinated, nitrated and sulphonated. On vigorous reduction the molecule splits at the azo group to give two molecules of primary amines, e.g. bcnzene-azophenol gives PhNH2 and p-HOC H NHa. 

The diazoamino-compounds are usually yellow in colour, and do not dissolve in acid they can usually be isolated and crystallized without decomposition. When treated with HNO2 two molecules of diazonium salt are formed. Form an azo compound when warmed with an amine and its hydrochloride, e.g. 

The most important reaction of the diazonium salts is the condensation with phenols or aromatic amines to form the intensely coloured azo compounds. The phenol or amine is called the secondary component, and the process of coupling with a diazonium salt is the basis of manufacture of all the azo dyestuffs. The entering azo group goes into the p-position of the benzene ring if this is free, otherwise it takes up the o-position, e.g. diazotized aniline coupled with phenol gives benzeneazophenol. When only half a molecular proportion of nitrous acid is used in the diazotization of an aromatic amine a diazo-amino compound is formed. 

The most noteworthy reaction of azo-compounds is their behaviour on reduction. Prolonged reduction first saturates the azo group, giving the hydrazo derivative (C NH-NH C), and then breaks the NH NH linkage, with the formation of two primary amine molecules. If method (1) has been employed to prepare the azo-compound, these two primary amines will therefore be respectively (a) the original amine from which the diazonium salt was prepared, and (6) the amino derivative of the amine or phenol with which the diazonium salt was coupled. For example, amino-azobenzene on complete reduction gives one equivalent of aniline, and one of p-phenylene diamine, NHaCeH NH benzene-azo-2-naphthoI similarly gives one equivalent of aniline and one of... 

Azo compounds may be identified by examination of the amine(s) formed on reduction in acid solution (see Sections IV,76 and IV,78) ... 

Supplement 1942 195-449 Hydroxy-amines Aminoethyl alcohol, 274. Carbonyl-amines Aminoacetaldehyde, 307. Aminoacetone, 314. Hydroxy-carbonyl amines Glucosamine, 328. Aminocarboxylic acids Glycine, 333. Hydroxylamines, 534. Hydrazines, 546. Azo Compounds. 562. Oryano-metallic Compounds, 580. 

Supplement 1952 2504-2665 Furfuracrylic acid, 300. Sulphonic acids, 667. Amines, 683. Hydroxylamines, 637. Hydrazines, 639. Azo compounds, 643. Diazo compounds, 661. Carbon-metal compounds, 663. 

Supplement 1953 3242-3457 Hydroxy-carboxylic acids, 190 In i doxylic acid, 226. Carbonyl-carboxylic acids, 284. i Sulphonic acids, 386 Quinoline sul-phonic acid, 390. Amines, 419 2-Aminopyridine, 428. Amino-carboxylic acids, 541 Tryp- tophane, 545. Hydrazines, 563. Azo. compounds, 572. Diazo compounds, 590. ... 

Supplement 1955 3634-3793 Sulphonic acids Indigo-disulphonic acid (indigocarmine), 304. Amines, 308. Keto-ammes Pyramidone, 452. Allan-toin, 474. Murexide, 499. Amino-carboxylic acids Histidine, 513. j Hydrazines, 531. Azo compounds, 535. 1... 

Reaction with arenediazonium salts Adding a phe nol to a solution of a diazonium salt formed from a primary aromatic amine leads to formation of an azo compound The reaction is carried out at a pH such that a significant portion of the phenol is pres ent as its phenoxide ion The diazonium ion acts as an electrophile toward the strongly activated ring of the phenoxide ion... 

Hydroperoxides have been obtained from the autoxidation of alkanes, aralkanes, alkenes, ketones, enols, hydrazones, aromatic amines, amides, ethers, acetals, alcohols, and organomineral compounds, eg, Grignard reagents (10,45). In autoxidations involving hydrazones, double-bond migration occurs with the formation of hydroperoxy—azo compounds via free-radical chain processes (10,59) (eq. 20). 

The first-order decomposition rates of alkyl peroxycarbamates are strongly influenced by stmcture, eg, electron-donating substituents on nitrogen increase the rate of decomposition, and some substituents increase sensitivity to induced decomposition (20). Alkyl peroxycarbamates have been used to initiate vinyl monomer polymerizations and to cure mbbers (244). They Hberate iodine quantitatively from hydriodic acid solutions. Decomposition products include carbon dioxide, hydrazo and azo compounds, amines, imines, and O-alkyUiydroxylarnines. Many peroxycarbamates are stable at ca 20°C but decompose rapidly and sometimes violently above 80°C (20,44). 

Although this reduction is more expensive than the Bnchamp reduction, it is used to manufacture aromatic amines which are too sensitive to be made by other methods. Such processes are used extensively where selectivity is required such as in the preparation of nitro amines from dinitro compounds, the reduction of nitrophenol and nitroanthraquinones, and the preparation of aminoazo compounds from the corresponding nitro derivatives. Amines are also formed under the conditions of the Zinin reduction from aromatic nitroso and azo compounds. 

The initiatoi is usually an azo compound and the sulfonation catalyst is usually a teitiaiy amine, ie, pyridine. Sulfuiyl chloride and chlorine may be used... 

Among the reagents that are classified as weak electrophiles, the best studied are the aromatic diazonium ions, which reagents react only with aromatic substrates having strong electron-donor substituents. The products are azo compounds. The aryl diazonium ions are usually generated by diazotization of aromatic amines. The mechanism of diazonium ion formation is discussed more completely in Section 11.2.1 of Part B. 

Methyl Orange.--The first point to notice in this reaction is that the diazonium salt forms no diazoamino-compotind with the dimethylanilinc, but at once pioduces an azo-compound. This is always the case with tertiary amines, some secondary amines like diphenyl.amine and the phenols. The reaction may be regarded as typical of the formation of all azo-colounng m.atters. At least two substances are requisite in this process on the one hand. an aromatic compound containing an amino-groujD in the nucleus, and, on the other, a base or phenol... 

The fonnadoo of C-N bonds can be achieved by using chkmumoe or O-methylhydrosylamine to yield primary amines aiyl diazonium salts yield azo-compounds ... 

Arenediazonium ions 1 can undergo a coupling reaction with electron-rich aromatic compounds 2 like aryl amines and phenols to yield azo compounds 3. The substitution reaction at the aromatic system 2 usually takes place para to the activating group probably for steric reasons. If the para position is already occupied by a substituent, the new substitution takes place ortho to the activating group. 

Atorvastatin, structure of, 105. 516 ATP (see Adenosine triphosphate) ATZ, see Anilinothiazolinone, 1031-1032 Aufbau principle. 6 Axial bonds (cyclohexane), 119 drawing, 120 Azide, amines from, 929 reduction of, 929 Azide synthesis, 929 Azo compound, 944 synthesis of, 944-945 uses of. 945... 

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