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.

Large Intermediates in Hydrazine Decomposition: A Theoretical Study of the N3H5 and N4H6 Potential Energy Surfaces

“…Hydrazine and hydrazine-based fuels such as monomethyl hydrazine are more commonly used as bipropellants with N 2 O 5 as the oxidizer. Hydrazine is used in thruster engines for attitude and in-orbit control of satellites and spacecraft, 1 where it is being stored and utilized at a maximal pressure of about 25 bar. [5][6][7] No detailed kinetic models for hydrazine-based fuels combustion in N 2 O 5 exist in the current literature; a step towards this goal is understanding hydrazine decomposition better.…”

Experimental and quantum chemical calculational studies on N‐[4‐(3‐Methyl‐3‐phenyl‐cyclobutyl)‐thiazol‐2‐yl]‐N′‐pyridin‐3ylmethylene‐hydrazine

“…Substituted hydrazines have found many scientific and commercial applications 1, 2. The importance of hydrazine derivatives is reflected in the great number of such compounds synthesized to date, and the synthesis of substituted hydrazines has been the subject of many studies 3–6.…”

Group X Aldehyde Dehydrogenases of Pseudomonas aeruginosa PAO1 Degrade Hydrazones

“…An alkaloid containing a hydrazone has also been isolated from a marine sponge (18). Hydrazones also involve many chiral building blocks, and they are applied in the agrochemical, pharmaceutical, and chemical industries (15). Hydrazones with replacement of R 2 and R 3 with hydrogen atoms, as used herein, involve many synthetic and natural compounds (9,15,18), but most of their physiological roles and biosynthetic mechanisms are unknown.…”

“…Hydrazones also involve many chiral building blocks, and they are applied in the agrochemical, pharmaceutical, and chemical industries (15). Hydrazones with replacement of R 2 and R 3 with hydrogen atoms, as used herein, involve many synthetic and natural compounds (9,15,18), but most of their physiological roles and biosynthetic mechanisms are unknown. We recently found that the yeast Candida palmioleophila MK883 produces hydrazone dehydrogenase (HDH) and assimilates hydrazones, such as adipic acid bis(ethylidene hydrazide) (AEH) and valeric acid ethylidene hydrazide (VEH) (3).…”