Hydrazine compounds

It must be noted, however, that nitroso, azoxy and azo compounds when subjected to the same treatment yield res])ectively hydroxylamines, hydrazo and hydrazine compounds, all of which reduce ammoniacal silver nitrate solution in the cold. 

Tetrahydroimidazo[5,l-c][l,2,4]triazine 474 was prepared (79KGS1540) by treating imidazole derivatives 472 or 473 with hydrazine. Compound 473 was obtained by reaction of the respective imidazole with 1,2-dibromoethane or by the reaction of the alcohol derivative 471 with phosphorus tribromide. On the other hand, chlorination of471 with thionyl chloride gave 472 (Scheme 100). 

The potential for toxicity that is associated with the administration of the MAOIs restricts their use in major depression. Hepatotoxicity is likely to occur with isocarboxazid or phenelzine, since hydrazine compounds can cause damage to hepatic parenchymal cells. This is true particularly for patients identified as slow acetyla-tors (see Chapter 4) of hydrazine compounds. Fortunately, the incidence of hepatotoxicity is low with the available agents. 

Hydrazine compounds are widely used as fuels, corrosion inhibitors, catalysts, and dyes. However, such compounds are recognized as toxic agents consequently, their detection and processing are of much concern. Only a few recent papers pertain to the catalytic oxidation of hydrazine [148-150], with special emphasis... 

Three potentiometric methods of analysis of hydrazine compounds are described ... 

Properties. 1. Pour 5 ml of water into each of two test tubes, and introduce 2-3 drops of hydrazine, hydrazine hydrate, or several crystals of hydrazine sulphate into them. Add several drops of iodine water into one tube. What is observed Write the equation of the reaction. Add solutions of copper(II) chloride and an alkali into the other tube. Carefully heat its contents. What happens Write the equation of the reaction. What properties do hydrazine compounds have ... 

Heinemann, B. (1971) Prophage induction in lysogenic Escherichia coli with simple hydroxyl-amine and hydrazine compounds. Appl. Microbiol., 21, 726-731... 

MacRae, W.D. Stich. H.F. (1979) Induction of sister-chromatid exchanges in Chinese hamster ovary cells by thiol and hydrazine compounds. Mutat. Res., 68, 351-365... 

Heat stabilizers can be selected from benzothiazoles, benzimidazoles hydrazine compounds, and cation exchange materials (73). Moreover, the addition of heat stabilizers results in an improvement of the impact resistance. 

J. Wang, M.P. Chatrathi and B. Tian, Capillary electrophoresis chips with thick-film amperometric detectors Separation and detection of hydrazine compounds, Electroanalysis, 12 (2000) 691-694. 

As in the previous section a hydrazine compound has been used to build other polynitrogen heterocycles (109a-b). In this case, the hydrazine is incorporated into a ring as V-amino-1,2,3-triazolo[4,5-d]pyrimidine (108) (Equation (7)) <90CZ246>. 

To manufacture this hydrazine compound, the hydrazine is placed in a container that would hold five times the amount of hydrazine being used. CAUTION Hydrazine is a dangerous chemical and ALL and any contact what so ever should be avoided. 

Primary amines form Schiff bases, (CH )2C=NR. Ammonia induces an aldol condensation followed by 1,4-addition of ammonia to produce diacetone amine (from mesityl oxide), 4-amino-4-methyl-2-pentanone [625-04-7], (CH3)2C(NH2)CH2COCH3, and triacetone amine (from phorone), 2,2,6,6-tetramethyl-4-piperidinone [826-36-8]. Hydroxylamine forms the oxime and hydrazine compounds (RNHNHJ form hydrazones (RNHN=C(CH3)2). Acetone and nitrous acid give the isonitroso compound which is the monoxime of pymvaldehyde [306-44-5], CH COCH=NOH. 

What now is the constitution of these diazo compounds The facts thus far considered and which must be explained by an accepted constitutional formula are, (i) Their formation by the action of nitrous acid on a primary- amine, (2) Their conversion into azo, amino azo, hydroxy azo and hydrazine compounds and (3) the basic character of the hydroxy compound, diazo benzene, and the true salt character of the compounds formed with strong acids. 

Table 6 Representative actinide(IV) amine and hydrazine compounds.

The biotransformation of hydrazine and hydrazide derivatives also proceeds by acetylation. The antihypertensive hydralazine (Apresoline) " ""and the MAO inhibitor phenelzine (Nardil) " are two representative hydrazine compounds that are metabolized by this pathway. The initially formed N-acetyl derivative of hydralazine is unstable and cyclizes intramolecularly to form 3-methyl-s-triazolo 3.4-a phtha-lazine as the major isolable hydralazine metabolite in humans. " The antituberculosis drug isoniazid or isonicoli-nic acid hydrazide (INH) is metabolized extensively to N-acetylisoniazid. " ... 

Methanol produced in the reaction also became a factor, as it reacted with the fully substituted hydrazine compound 9. Methanolysis tended to occur mainly at N-1. This allowed for selective production of either 8 or 9 by adding or removing methanol respectively, facilitating or circumventing the methanolysis process (Table 10, entries 2 and 3). 

This document uses the term "hydrazines" to refer to hydrazine, 1,1-dimethylhydrazine, and 1,2-dimethylhydrazine, collectively. These hydrazines are somewhat similar in chemical structure and reactivity. However, there are some clear differences in their production, uses, and adverse health effects. There are many other hydrazine compounds however, these three hydrazines are discussed together in this document because they are of interest to the U.S. Department of Defense. 

NIOSH. 1977b. Hydrazine compounds in air - method 248. In NIOSH manual of analytical methods. 2nd ed. Vol. 1. Cincinnati, OH National Institute for Occupational Safety and Health, Centers for Disease Control. 

Preece NE, Timbrell JA. 1989. Investigation of lipid peroxidation induced by hydrazine compounds in vivo in the rat. Phannacol Toxicol 64 282-285. 

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