Carbohydrazide is the
chemical compound
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one ele ...
with the formula OC(N
2H
3)
2. It is a white, water-soluble solid.
It decomposes upon melting.
A number of
carbazides are known where one or more N-H groups are replaced by other substituents. They occur widely in the drugs, herbicides, plant growth regulators, and dyestuffs.
Production
Industrially the compound is produced by treatment of
urea
Urea, also known as carbamide, is an organic compound with chemical formula . This amide has two amino groups (–) joined by a carbonyl functional group (–C(=O)–). It is thus the simplest amide of carbamic acid.
Urea serves an important ...
with
hydrazine
Hydrazine is an inorganic compound with the chemical formula . It is a simple pnictogen hydride, and is a colourless flammable liquid with an ammonia-like odour. Hydrazine is highly toxic unless handled in solution as, for example, hydrazin ...
:
[Jean-Pierre Schirmann, Paul Bourdauducq "Hydrazine" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2002. .]
:OC(NH
2)
2 + 2 N
2H
4 → OC(N
2H
3)
2 + 2 NH
3
It can also be prepared by reactions of other C1-precursors with
hydrazine
Hydrazine is an inorganic compound with the chemical formula . It is a simple pnictogen hydride, and is a colourless flammable liquid with an ammonia-like odour. Hydrazine is highly toxic unless handled in solution as, for example, hydrazin ...
, such as
carbonate ester
In organic chemistry, a carbonate ester (organic carbonate or organocarbonate) is an ester of carbonic acid. This functional group consists of a carbonyl group flanked by two alkoxy groups. The general structure of these carbonates is and they ...
s.
It can be prepared from
phosgene
Phosgene is the organic chemical compound with the formula COCl2. It is a toxic, colorless gas; in low concentrations, its musty odor resembles that of freshly cut hay or grass. Phosgene is a valued and important industrial building block, es ...
, but this route cogenerates the
hydrazinium salt
2H5l and results in some diformylation. Carbazic acid is also a suitable precursor:
:N
2NH
3CO
2H + N
2H
4 → OC(N
2H
3)
2 + H
2O
Structure
The molecule is nonplanar. All nitrogen centers are at least somewhat pyramidal, indicative of weaker C-N pi-bonding. The C-N and C-O distances are about 1.36 and 1.25 Å, respectively.
[Ottersen, T.; Hope, H. "The Structure and Electron Deformation Density Distribution of Carbonohydrazide (Carbohydrazide) at 85 K" Acta Crystallographica B 1979, volume 35, p373-p378. ]
Industrial uses
* Oxygen scrubber: carbohydrazide is used to remove oxygen in boiler systems. Oxygen scrubbers prevent corrosion.
* Precursor to polymers: carbohydrazide can be used as a curing agent for epoxide-type resins.
* Photography: carbohyrazide is used in the silver halide diffusion process as one of the toners. Carbohydrazide is used to stabilize color developers that produce images of the azo-methine and azine classes.
* Carbohydrazide has been used to develop ammunition propellants,
stabilize soaps,
and is used as a reagent in organic synthesis.
Hazards
Heating carbohydrazide may result in an explosion. Carbohydrazide is harmful if swallowed, irritating to eyes, respiratory system, and skin. Carbohydrazide is toxic to aquatic organisms.
References
{{Hydrazines
Cleaning product components
Hydrazides