Azoxy compounds, detection

These radical anions have been detected by ESR. This mechanism is consistent with the following result when nitrosobenzene and phenylhydroxylamine are coupled, and N labeling show that the two nitrogens and the two oxygens become equivalent. Unsymmetrical azoxy compounds can be prepared by combination of a nitroso compound with an N,N-dibromoamine. Symmetrical and unsymmetrical azo and azoxy compounds are produced when aromatic nitro compounds react with aryliminodimagnesium reagents, ArN(MgBr>2. ... 

Traces of azo compounds were detected in the reaction mixture. They probably were formed by the reduction of the azoxy compound by the Grignard reagent. 

Metabolism studies on 1,2-dimethylhydrazine in vivo led to the mechanism of metabolic activation outlined in Fig. 18 (725). Unlike monoalkylated hydrazines, 1,2-disubstituted hydrazines appear to form azo and azoxy compounds which act as proximate carcinogens. In the case of 1,2-dimethylhydrazine, azoxymethane and methylazoxymethanol were detected in the urine of treated rats 126). Studies on the metabolic fate of procarbazine in vivo have also shown that dealkylation occurs 108, 109). 

The study of the produets of the 2- and 4-(4 -azidostyryl)quinolines photolysis by the electrospr mass spectrometry showed that, as a result of the photodissoeiation of the N-N2 bond, a set of products typical of the azide photoehemistry were formed corresponding arrrines, rritroso, nitro, azo, hydrazo, and azoxy compounds (the last three in insigrriflcant amormts) [74], In the azide photolysis in the presenee of HCl, the ratio of these products changed, and the ehlorine-eontaining eompotmds were formed in addition. There were some produets, whieh eould not be identified by mass spectrometry. In addition, the formation of unsubstituted styrylquinolines was also detected. This finding indicated the photodissoeiation of the C-N3 bond, a proeess that is imeonventional in the photochemistry of aromatic azides. 

In addition to the detection of the azoxy group in the molecule by the rearrangement of the substance to hydroxyazobenzenes, the N=N bond can be cleaved, as in azo compounds, by an energetic reduction with Zn or SnCl2 in an acid medium (50). 

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