Hydrazide
Hydrazides in organic chemistry are a class of organic compounds sharing a common functional group characterized by a nitrogen to nitrogen covalent bond with 4 substituents with at least one of them being an acyl group. The general structure for a hydrazide is E(=O)-NR-NR2, where the R's are frequently hydrogens. Hydrazides can be further classified by atom attached to the oxygen: carbohydrazides (R-C(=O)-NH-NH2), sulfonohydrazides (R-S(=O)2-NH-NH2), and phosphonic dihydrazides (R-P(=O)(-NH-NH2)2. The related hydrazines do not carry an acyl group. Some important members of this class are sulfonylhydrazides such as p-toluenesulfonylhydrazide which are useful reagents in organic chemistry such as in the Shapiro reaction and the Eschenmoser–Tanabe fragmentation. This reagent can be prepared by reaction of tosyl chloride with hydrazine.
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