Hydrazine and Its Derivatives

Abstract

Hydrazine (diamide), N 2 H 4 , a colorless liquid having an ammoniacal odor, is the simplest diamine and unique in its class because of the N—N bond. Hydrazine and its simple methyl and dimethyl derivatives have endothermic heats of formation and high heats of combustion. Hence these compounds are used as rocket fuels. Other derivatives are used as gas generators and explosives. Hydrazine, a base slightly weaker than ammonia, forms a series of useful salts. As a strong reducing agent, hydrazine is used for corrosion control in boilers and hot‐water heating systems; also for metal plating, reduction of noble‐metal catalysts, and hydrogenation of unsaturated bonds in organic compounds. Hydrazine is also an oxidizing agent under suitable conditions. Having two active nucleophilic nitrogens and four replaceable hydrogens, hydrazine is the starting material for many derivatives, among them foaming agents for plastics, antioxidants, polymers, polymer cross‐linkers and chain‐extenders, as well as fungicides, herbicides, plant‐growth regulators, and pharmaceuticals. Hydrazine is also a good ligand; numerous complexes have been studied. Many heterocyclics are based on hydrazine, where the rings contain from one to four nitrogen atoms as well as other heteroatoms. The many advantageous properties of hydrazine assure continued‐commercial utility. Hydrazine is available in anhydrous form as well as aqueous solutions, typically 35, 51.2, 54.4, and 64 wt % N 2 H 4 (54.7, 80, 85, and 100% hydrazine hydrate). The commercially feasible processes involve partial oxidation of ammonia (or urea) using hypochlorite or hydrogen peroxide. Most hydrazine is produced by some variation of the Raschig process, which is based on the oxidation of ammonia using alkaline hypochlorite. Hydrazine is toxic and readily absorbed by oral, dermal, or inhalation routes of exposure.

Oxidizer−Fuel Interactions in Aqueous Combustion Synthesis. 1. Iron(III) Nitrate−Model Fuels

“…The normalized −Δ H c values for the different fuels do not differ significantly. The only exception is hydrazine, a well-known fuel in propellant applications . Along with concentrated nitric acid, hydrazine forms a hypergolic mixture, i.e., ignites without any external energy source.…”

Effect of Oscillatoria willei – a Marine Cyanobacterium on Hydrazine Induced Toxicity

“…Hydrazine is a base, slightly weaker in strength than ammonia that can function as a strong reducing agent or as an oxidizing agent under certain conditions (Schiessl, 1995). At ambient temperature, hydrazine is a fuming, colorless, oily, hygroscopic liquid with an ammonia-like odor (National Research Council, 1996).…”

“…At ambient temperature, hydrazine is a fuming, colorless, oily, hygroscopic liquid with an ammonia-like odor (National Research Council, 1996). Hydrazine has numerous industrial applications (Schiessl, 1995). It is used in the synthesis of many derivatives, including foaming or blowing agents, polymers, antioxidants, fungicides, herbicides, insecticides, plant growth regulators, and pharmaceuticals, such as the antibiotic isoniazid.…”

Hydrazidase, a Novel Amidase Signature Enzyme That Hydrolyzes Acylhydrazides

“…Hydrazine derivatives containing an unsubstituted -NH 2 moiety are dehydrated and condensed with carbonyl compounds to generate hydrazones. Acylated derivatives of hydrazine are described as R 1 R 2 N-N(R 3 )C(ϭO)R 4 and are called (acyl)hydrazides. One of the most popular hydrazides is isonicotinic acid hydrazide (INH), an antituberculosis agent that has been clinically applied and marketed under the name isoniazid (1).…”

“…For example, maleic hydrazide has been extensively applied as a plant growth regulator and herbicide, especially in the cultivation of tobacco, potatoes, and onions. The industrial uses of hydrazides include cross-linking acrylic emulsions, curing epoxy resins, and scavenging formaldehyde through their powerful reactivity with ketone and epoxy groups (4).…”