1,2-ДИФЕНИЛГИДРАЗИН

Описание

Diphenylhydrazine is a man-made chemical that occurs in two isomeric forms: 1,1-diphenylhydrazine and 1,2-diphenylhdrazine. Diphenylhydrazine is produced by the reduction of nitrobenzene. Little or no information is available for 1,1-diphenylhydrazine. Most toxicological and use data pertain to 1,2-diphenylhydrazine.

Химические свойства

yellow crystalline powder

Использование

Previously, 1,2-diphenylhydrazine was used for producing benzidine that was used in the synthesis of benzidine-based dyes. However, these dyes are no longer produced in the United States. The primary use of 1,2-diphenylhydrazine is in the production of the anti-inflammatory agent phenylbutazone and sulfinpyrazone, a uricosuric agent.

Общее описание

Orange powder or a bright orange crystalline solid.

Реакции воздуха и воды

1,2-Diphenylhydrazine oxidizes in air. 1,2-Diphenylhydrazine decomposes in acid solutions. Insoluble in water.

Профиль реактивности

1,2-Diphenylhydrazine is a mild reducing agent. Incompatible with strong oxidizing agents, strong acids, acid chlorides and acid anhydrides. Interaction with perchloryl fluoride in the presence of a dilutent below 32°F has caused separation of explosive solids. Is readily oxidized by nitric acid, silver nitrate or permanganate. Is reduced under alkaline conditions .

Угроза здоровью

1,2-Diphenylhydrazine is a liver toxin in rodents and appears to be carcinogenic in experimental animals.

Пожароопасность

Flash point data for 1,2-Diphenylhydrazine are not available; however, 1,2-Diphenylhydrazine is probably combustible.

Канцерогенность

Hydrazobenzene is reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in experimental animals.

Экологическая судьба

Biological. When 5 and 10 mg/L of diphenylhydrazine was statically incubated in the dark at 25 °C with yeast extract and settled domestic wastewater inoculum, 80 and 72% biodegradation, respectively, were observed after 7 d (Tabak et al., 1981).
Chemical/Physical. Wet oxidation of 1,2-diphenylhydrazine at 320 °C yielded formic and acetic acids (Randall and Knopp, 1980). 1,2-Diphenylhydrazine will not hydrolyze (Kollig, 1993).
At influent concentrations of 1.0, 0.1, 0.01, and 0.001 mg/L, the GAC adsorption capacities were 16,000, 160, 1.5, and 0.015 mg/g, respectively (Dobbs and Cohen, 1980).

Методы очистки

Crystallise hydrazobenzene from hot EtOH containing a little ammonium sulfide or H2SO3 (to prevent atmospheric oxidation), preferably under N2. Dry it in a vacuum desiccator, and store it in the dark or under N2. Alternatively, crystallise it from pet ether (b 60-100o) to constant absorption spectrum. It is almost colourless but in air it turns yellow, then red with the formation of azobenzene. The hydrochloride crystallises from EtOH and has m 163-164o(dec); however, hydrazobenzene readily rearranges to benzidine in the presence of acid. The picrate crystallises from *C6H6 and has m 123o(dec). [Beilstein 15 H 123.]