diazonium salt

diazonium salt
any of a group of salts of the general formula ArN2X, in which Ar represents an aryl group and X an anion, as benzenediazonium chloride, C6H5N(N)Cl, many of which are important intermediates in the manufacture of azo dyes.
[1905-10]

* * *

      any of a class of organic compounds that have the molecular structure

      in which R is an atomic grouping formed by removal of a hydrogen atom from an organic compound. Diazonium salts are usually prepared by the reaction (diazotization) of primary amines (amine) with nitrous acid; their most striking property is their instability. The aliphatic diazonium salts exist only as transient intermediates, quickly decomposing into a nitrogen molecule and a carbonium ion; certain aromatic diazonium salts are stable enough to be isolated but react readily either by loss of nitrogen or by formation of azo compounds (azo compound).

      Diazonium salts were first obtained from aromatic amines in 1858, and their utility in the preparation of azo compounds was soon recognized by the dye industry. By varying the chemical structures of the amines that are diazotized (the diazo components) and of the compounds with which they react (the coupling components), colours throughout the visible spectrum are imparted to dyes applicable to many types of fibres by several techniques.

      The diazonium group can be replaced by numerous atoms or groups of atoms, often with the aid of copper or a copper salt; these reactions make possible the preparation of a wide variety of aromatic derivatives. Chemical reduction of aromatic diazonium salts leads to formation of hydrazine derivatives.

* * *


Universalium. 2010.

Игры ⚽ Нужно решить контрольную?

Look at other dictionaries:

  • diazonium salt — noun a diazonium compound …   Wiktionary

  • diazonium salt — /daɪəˌzoʊniəm ˈsɒlt/ (say duyuh.zohneeuhm solt) noun any salt of the general formula R N2+, where R is an aromatic or aliphatic group; an important intermediate in the manufacture of dyes …  

  • diazonium salt — Chem. any of a group of salts of the general formula ArN2X, in which Ar represents an aryl group and X an anion, as benzenediazonium chloride, C6H5N(N)Cl, many of which are important intermediates in the manufacture of azo dyes. [1905 10] …   Useful english dictionary

  • Diazonium compound — Phenyldiazonium cation Diazonium compounds or diazonium salts are a group of organic compounds sharing a common functional group R N2+ X where R can be any organic residue such alkyl or aryl and X is an inorganic or organic anion such as a… …   Wikipedia

  • diazonium compound — noun any compound having the general formula R N X, especially one in which R is an aryl residue; they are important as intermediates in the production of azo dyes Syn: diazonium salt …   Wiktionary

  • Salt — In medicine, salt usually refers to sodium chloride, table salt, used for seasoning food, for the preservation of meat, etc. Salt is found in the earth and in sea water and is isolated by evaporation and crystallization from sea water and other… …   Medical dictionary

  • organohalogen compound — Introduction  any of a class of organic compounds (organic compound) that contain at least one halogen (halogen element) ( fluorine [F], chlorine [Cl], bromine [Br], or iodine [I]) bonded to carbon. They are subdivided into alkyl, vinylic, aryl,… …   Universalium

  • Amine — For other uses, see Amine (disambiguation). Primary amine Secondary amine Tertiary amine …   Wikipedia

  • photography, technology of — Introduction       equipment, techniques, and processes used in the production of photographs.  The most widely used photographic process is the black and white negative–positive system (Figure 1 >). In the camera the lens projects an image of… …   Universalium

  • Meerwein arylation — The Meerwein arylation is an organic reaction involving the addition of an aryl diazonium salt (ArN2X) to an electron poor alkene usually supported by a metal salt.[1] The reaction product is an alkylated arene compound. The reaction is named… …   Wikipedia

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”