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Osazone formation was developed by Emil Fischer, [3] who used the reaction as a test to identify monosaccharides. The formation of a pair of hydrazone functionalities involves both oxidation and condensation reactions. [4] Since the reaction requires a free carbonyl group, only "reducing sugars" participate.
Phenylhydrazine was the first hydrazine derivative characterized, reported by Hermann Emil Fischer in 1875. [ 7 ] [ 8 ] He prepared it by reduction of a phenyl diazonium salt using sulfite salts. Fischer used phenylhydrazine to characterize sugars via formation of hydrazones known as osazones with the sugar aldehyde .
R 2 C=N−NR' 2 + H 2 O → R 2 C=O + H 2 N−NR' 2. Alkyl hydrazones are 10 2 - to 10 3-fold more sensitive to hydrolysis than analogous oximes. [10] When derived from hydrazine itself, hydrazones condense with a second equivalent of a carbonyl to give azines: [11] R 2 C=N−NH 2 + R 2 C=O → R 2 C=N−N=CR 2 + H 2 O. Hydrazones are ...
Hydrazines (R 2 N−NR 2) are a class of chemical compounds with two nitrogen atoms linked via a covalent bond and which carry from one up to four alkyl or aryl substituents. Hydrazines can be considered as derivatives of the inorganic hydrazine (H 2 N−NH 2), in which one or more hydrogen atoms have been replaced by hydrocarbon groups. [1]
2,4-Dinitrophenylhydrazine (2,4-DNPH or DNPH) is the organic compound C 6 H 3 (NO 2) 2 NHNH 2. DNPH is a red to orange solid. It is a substituted hydrazine. The solid is relatively sensitive to shock and friction. For this reason DNPH is usually handled as a wet powder. DNPH is a precursor to the drug Sivifene.
Phenazone is synthesized [7] by condensation of phenylhydrazine and ethyl acetoacetate under basic conditions and methylation of the resulting intermediate compound 1-phenyl-3-methylpyrazolone [8] with dimethyl sulfate or methyl iodide. It crystallizes in needles which melt at 156 °C (313 °F).
N 2 H 4 + O 2 → N 2 + 2 H 2 O. An excess of oxygen gives oxides of nitrogen, including nitrogen monoxide and nitrogen dioxide: N 2 H 4 + 2 O 2 → 2 NO + 2 H 2 O N 2 H 4 + 3 O 2 → 2 NO 2 + 2 H 2 O. The heat of combustion of hydrazine in oxygen (air) is 19.41 MJ/kg (8345 BTU/lb). [57] Hydrazine is a convenient reductant because the by ...
The above photo shows the positive results of the number 2 Marquis reagent presumptive drug test when used with a sample of opium. It is the primary presumptive test used in Ecstasy reagent testing kits. It can also be used to test for such substances as opiates (e.g. codeine, heroin), and phenethylamines (e.g. 2C-B, mescaline).