Diazotization amines

Phloroglucinol is Hsted in the Colourindex as Cl Developer 19. It is particularly valuable in the dyeing of acetate fiber but also has been used as a coupler for azoic colors in viscose, Odon, cotton (qv), rayon, or nylon fibers, or in union fabrics containing these fibers (157). For example, cellulose acetate fabric is treated with an aromatic amine such as (9-dianisidine or a disperse dye such as A-hydroxyphenylazo-2-naphthylamine and the amine diazotizes on the fiber the fabric is then rinsed, freed of excess nitrite, and the azo color is developed in a phloroglucinol bath at pH 5—7. Depending on the diazo precursor used, intense blue to jet-black shades can be obtained with excellent light-, bleach-, and mbfastness. 

Nucleophilic substitution reactions that occur imder conditions of amine diazotization often have significantly different stereochemisby, as compared with that in halide or sulfonate solvolysis. Diazotization generates an alkyl diazonium ion, which rapidly decomposes to a carbocation, molecular nitrogen, and water ... 

Dyes are synthesized in a reactor, then filtered, dried, and blended with other additives to produce the final product. The synthesis step involves reactions such as sulfonation, halogenation, amination, diazotization, and coupling, followed by separation processes that may include distillation, precipitation, and crystallization. 

The reversibility of aromatic diazotization in methanol may indicate that the intermediate corresponding to the diazohydroxide (3.9 in Scheme 3-36), i. e., the (Z)-or (is)-diazomethyl ether (Ar — N2 — OCH3), may be the cause of the reversibility. In contrast to the diazohydroxide this compound cannot be stabilized by deprotonation. It can be protonated and then dissociates into a diazonium ion and a methanol molecule. This reaction is relatively slow (Masoud and Ishak, 1988) and therefore the reverse reaction of the diazomethyl ether to the amine may be competitive. Similarly the reversibility of heteroaromatic amine diazotizations with a ring nitrogen in the a-position may be due to the stabilization of the intermediate (Z)-diazohydroxide, hydrogen-bonded to that ring nitrogen (Butler, 1975). However, this explanation is not yet supported by experimental data. 

Phosphoryl-substituted diazo compounds of general type 4 have recently been synthesized by amine diazotization, Bamford-Stevens reaction, and diazo group... 

Formation of chloroquinazolines by amine diazotization can also been performed, but in the case of 4-amino-2-chloro-5-iodo-6,7-dimethoxyquinazoline 122, chlorination with isobutyl nitrite and cupric chloride to give 123 was accompanied by hydrolysis to the analogous quinazolinone 124 <2005TL983>. 

A colorimetric procedure for phenytoin developed by Dill et al24f provided the first reliable means for determining blood and tissue levels of this drug. The procedure involves quantitative nitration, reduction of the nitro group to a primary amine, diazotization and coupling with the Bratton-Marshall reagent. 

Amines Diazotization Hinsberg test Solubility in dilute HCI All 1° amines give red azodyes with [i-naphthol Distinguishes between 1°, 2°, and 3° All amines are soluble... 

Acidified potassium permanganate efficiently degrades aromatic amines. Diazotization followed by hypophosphorus acid protonation is a method for deamination of aromatic amines, but the procedure is more complex than oxidation. 

Diazotization involves drawing a known volume of atmospheric air through an absorbent solution, hydrolyzing the isocyanate to amine, diazotization and coupling this amine, and comparison of colour formation with a range of standards. The method varies in detail with the specific isocyanate being determined. 

This correlation (Scheme 13.10) had originally been performed by Leithe,W. Chem. Ber., 1931, (54,2827 by benzoylation of the (-)-l-phenylethylamine, nitration of the aromatic ring of the resulting At-benzoyl derivative, reduction of the nitro group to the amine, diazotization of the amine and conversion of the diazo compound to the phenol. Oxidation of the phenol with chromic anhydride in acetic acid yielded the A -benzoyl derivative of (-F)-alanine—by direct comparison to that compound. 

Hydrocarbon Forming Pathways from Amine Diazotizations. J. Amer. Chem. 

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