2.6- Dinitrobenzaldehyde hydrazones

A -Nitroso compounds can be easily reduced to their hydrazines, which are further derivatized. The most satisfactory approach is the conversion of the hydrazine to its 3,5-dinitrobenzaldehyde hydrazone, which is then analyzed using GC with electron capture detection." ... 

The isolation of the liberated carbonyl compounds is carried out, depending on their character, by filtration, extraction, steam distillation, or other means. Hydrazones can also be split by the expulsion of the carbonyl compound by a more reactive aldehyde, as, for example, benzaldehyde, p-nitrobenzaldehyde, 2,4-dinitrobenzaldehyde, and formaldehyde. The use of nonvolatile levulinic acid (81) is advantageous. In cases where the aldehyde formed on hydrolytic cleavage is unstable under the given conditions... 

The carbonyl compounds are isolated by separation, extraction, or steam distillation, depending on their nature. They can also be cleaved by expelling the carbonyl compound with a more reactive aldehyde benzal-dehyde is most commonly used, but p-nitrobenzaldehyde, 2,4-dinitroben-zaldehyde, and formaldehyde can be used as well (97 — 99). The expulsion of 2,4-dinitrobenzaldehyde from its hydrazone can be carried out with glyoxal or diacetyl (100). 

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