Diazo- and Diazonium Compounds

Diazonium salts and aliphatic diazo compounds can easily be named following the instructions layed down in Tables 6 and 8. 

H3C-CHN2 Diazoethane C6H5-CO-CHN2 2-Diazo-l-phenyl- 

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Dediazoniation refers to all those reactions of diazo and diazonium compounds in which an N2 molecule is one of the products. The designation of the entering group precedes the term dediazoniation, e. g., azido-de-diazoniation for the substitution of the diazonio group by an azido group, or aryl-de-diazoniation for a Gomberg-Bachmann reaction. The IUPAC system says nothing about the mechanism of a reaction (see Sec. 1.2). For example, the first of the two dediazoniations mentioned is a heterolytic substitution, whereas the second is a homolytic substitution. 

In this chapter the major emphasis is on the mechanistic aspects of dediazoniations because they are the basis for understanding the relative instability of diazo and diazonium compounds, and because a knowledge of these is helpful for optimizing synthetic applications of such compounds. Syntheses based on dediazoniation of arenediazonium salts are the subject of Chapter 10. 

How appropriate this statement is with regard to the electrochemistry of arenediazonium ions is evident in the chapter by Fry (1978) in the monograph on diazo and diazonium compounds of the Patai series. Arenediazonium salts are treated on two pages only ... 

To 1.1 gm (0.0038 mole) of bis(2-amino-5-nitrophenyl) ether dissolved in 10 ml of 5 TV hydrochloric acid and cooled to 0°-5°C by adding ice to the solution is slowly added 8 ml of a 0.1 TV solution of sodium nitrite (0.008 mole) while maintaining the temperature between 0° and 5°C. After the addition has been completed (see Volume I, Chapter 15, Diazo and Diazonium Compounds, for notes and precautions in carrying out diazotizations), stirring is continued for 1 hr (see Wistar and Bartlett [6] on the sluggishness of some diazotizations). 

Since many azides may be explosive compounds, investigators planning to work with them should consult the literature and take special precautions. See Volume I, Chapter 15, Diazo and Diazonium Compounds, for additional information about diazo hydrocarbons. 

For reviews, see Meier Zeller Angew. Chem. Int. Ed. Engl. 1975, 14, 32-43 [Angetv. Chem. 87, 52-63] Kirmse, Ref. 124, pp. 475-493 Rodina Korobitsyna Russ. Chem. Rev. 1967,36, 260-272 For a review of rearrangements of diazo and diazonium compounds, see Whittaker, in Patai The Chemistry of Diazonium and Diazo Compounds, pt. 2 Wiley New York, 1978, pp. 593-644. 

Diazo and Diazonium Compounds Fluoro-Substituted Aliphatics... 

DIAZO AND DIAZONIUM COMPOUNDS TABLE 109. DIAZO AND DIAZONIUM COMPOUNDS... 

Most diazo- and diazonium compounds are described in this Encyclopedia, either as individual diazocompds or under the corresponding parent compd, such as Benzene Diazo-and Diazonium Derivatives (Vol 2, pp B34-R to B58-L)... 

Hydrazones.—Oxidation of hydrazones with lead tetra-acetate gives nitrogen and a mixture of acetates and olefins, apparently through the intermediacy of diazo- and diazonium compounds (Scheme 18). The steroid hydrazone at C-7 affords mainly the 7a-acetoxy-derivative, but at C-3 a mixture of 3a- and 3j8-acetoxy-compounds results, together with an olefinic fraction. ... 

As there is a fairly large number of inorganic compounds that contain a primary amino group, it is of interest to briefly review how they react under the nitrosation conditions that are usually employed in the preparation of organic diazo and diazonium compounds. 

Reactions of Aliphatic Diazo and Diazonium Compounds not Involving Initial Dediazoniation... 

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