Diazotization


Also found in: Dictionary, Thesaurus, Medical.

diazotization

[dī‚az·ət·ə′zā·shən]
(organic chemistry)
Reaction between a primary aromatic amine and nitrous acid to give a diazo compound. Also known as diazo process.

Diazotization

 

the reaction of preparing diazo compounds by the action of nitrous acid (or its derivatives) on primary amines in the presence of inorganic acids (HCl, H2SO4, or HNO3) at 0°-5°C. The diazotization of aromatic amines to yield diazonium salts is the most common—for example, aniline is diazotized to phenyldiazonium chloride:

In organic synthesis, diazotization is used extensively to make various aromatic compounds through the diazonium salt, as well as to synthesize dyes, particularly azo dyes.

References in periodicals archive ?
(2) The electrochemical polymerization of 4-carboxyphenyl diazonium salts prepared by the diazotization reaction is a very simple and easy method for preparation of good biosensor supports.
5-phenyl-1,3,4-thiadiazole-2-amine was synthesized by single step reaction and it was transformed to its corresponding diazonium salt by diazotization reaction and was further coupled with various coupling agents (8-hydroxy quinoline, 2,6-diaminopyridine N,N-dimethyl aniline, 2-naphthol, resorcinol, and 4,6-dihydroxypyrimidine) under suitable experimental reaction.
Indirect flow injection voltammetric determination of sulphanilamide by monitoring at a glassy carbon electrode the excess of nitrite remaining after its diazotization has been reported by Fogg et a1 [55].
The absorbance of the chromophore formed during diazotization of the nitrite with sulphanilamide and subsequent coupling with N-1-naphthylethylene diamine dihydrochloride was measured at 546 nm and percentage scavenging activity was measured with reference to standard.
Methods: Partially purified Amaranthus spinosus leaf oxalate oxidase was immobilized through diazotization onto arylamine glass beads affixed on the surface of a plastic strip by a non reactive fixative and employed for oxalate determination in urine and serum samples collected from healthy individuals and urinary stone formers.
Bilirubin was measured on the Modular analyzer by a modified diazotization method using 2,5-dichlorophenyldiazonium tetrafluoroborate as the source of diazonium ion (Roche Diagnostics Corporation).
Ammonium-N ([NH.sub.4]-N) concentrations (by reaction with salicylate/nitroprusside) and [NO.sub.3]-N concentrations (by diazotization following hydrazine reduction) were measured on a Technicon AutoAnalyzer II system (Blakemore et al.
Diazotization of the amine produces a diazonium intermediate that is not isolated but is reduced with tin chloride to the corresponding hydrazine.
Concentrations of ammonium nitrogen ([NH.sub.4]-N) were determined using the phenol blue method, and concentrations of nitrate nitrogen ([NO.sub.3]-N) were determined by diazotization with sulfanilamide after reduction of nitrate to nitrite through a cadmium coil (Keeney and Nelson 1982).
Ammonium (salicylate/nitroprusside; Keeney and Nelson 1982) and N[[O.sub.3].sup.-] (diazotization following cadmium reduction; Keeney and Nelson 1982) were determined using an Alpkem RFA 300 Rapid Flow Analyzer (Clackamas, Oregon, USA).
Nitrate was reduced to nitrite using hydrazine sulphate and CuS[O.sub.4] catalyst and then analyzed colorimetrically by the Giess-Ilosvay reaction (diazotization).