Product Code Database
Hydroxylamine (also known as hydroxyammonia) is an inorganic compound with the chemical formula . The compound exists as hygroscopic colorless .Greenwood and Earnshaw. Chemistry of the Elements. 2nd Edition. Reed Educational and Professional Publishing Ltd. pp. 431–432. 1997. Hydroxylamine is almost always provided and used as an aqueous solution or more often as one of its salts such as hydroxylammonium sulfate, a water-soluble solid.
Hydroxylamine and its salts are consumed almost exclusively to produce Nylon-6. The Redox of Ammonia to hydroxylamine is a step in biological nitrification.
is mainly produced as its [[sulfuric acid]] salt, hydroxylammonium sulfate (), by the [[hydrogenation]] of [[nitric oxide]] over [[platinum]] [[catalyst]]s in the presence of sulfuric acid.
Hydroxylamine can also be produced by the reduction of nitrous acid or potassium nitrite with bisulfite:
A direct lab synthesis of hydroxylamine from Nitrogen in water plasma was demonstrated in 2024.
Base, such as sodium butoxide, can be used to free the hydroxylamine from hydroxylammonium chloride:
Hydroxylamine reacts with usually at the nitrogen atom:
The reaction of with an aldehyde or ketone produces an oxime.
reacts with chlorosulfonic acid to give hydroxylamine-''O''-sulfonic acid:
It to the amine oxide .
Similarly to amines, one can distinguish hydroxylamines by their degree of substitution: primary, secondary and tertiary. When stored exposed to air for weeks, secondary hydroxylamines degrade to .
Norganylhydroxylamines, , where R is an organyl group, can be reduced to :Smith, Michael and Jerry March. March's advanced organic chemistry : reactions, mechanisms, and structure. New York. Wiley. p. 1554. 2001.
Alkylation of hydroxylamine or N-alkylhydroxylamines proceeds usually at nitrogen. One challenge is dialkylation when only monoalkylation is desired.
Amine oxidation with benzoyl peroxide is a common method to synthesize hydroxylamines. Care must be taken to prevent over-oxidation to a nitrone. Other methods include:
High concentrations of hydroxylamine are used by biologists to introduce Mutagenesis by acting as a DNA nucleobase amine-hydroxylating agent. In is thought to mainly act via hydroxylation of cytidine to hydroxyaminocytidine, which is misread as thymidine, thereby inducing C:G to T:A transition mutations. But high concentrations or over-reaction of hydroxylamine in vitro are seemingly able to modify other regions of the DNA & lead to other types of mutations. This may be due to the ability of hydroxylamine to undergo uncontrolled free radical chemistry in the presence of trace metals and oxygen, in fact in the absence of its free radical effects Ernst Freese noted hydroxylamine was unable to induce reversion mutations of its C:G to T:A transition effect and even considered hydroxylamine to be the most specific mutagen known. Practically, it has been largely surpassed by more potent mutagens such as EMS, ENU, or nitrosoguanidine, but being a very small mutagenic compound with high specificity, it found some specialized uses such as mutation of DNA packed within bacteriophage capsids, and mutation of purified DNA in vitro.
Some non-chemical uses include removal of hair from animal hides and photographic developing solutions. In the semiconductor industry, hydroxylamine is often a component in the "resist stripper", which removes photoresist after lithography.
Hydroxylamine can also be used to better characterize the nature of a post-translational modification onto proteins. For example, poly(ADP-Ribose) chains are sensitive to hydroxylamine when attached to glutamic or aspartic acids but not sensitive when attached to serines. Similarly, Ubiquitin molecules bound to serines or threonines residues are sensitive to hydroxylamine, but those bound to lysine (isopeptide bond) are resistant.
Cytochrome P460, an enzyme found in the ammonia-oxidizing bacteria Nitrosomonas europea, can convert hydroxylamine to nitrous oxide, a potent greenhouse gas.
Hydroxylamine can also be used to highly selectively cleave asparagine-glycine peptide bonds in peptides and proteins. (1977). 9780121819477 ISBN 9780121819477 It also bonds to and permanently disables (poisons) Hemoprotein. It is used as an irreversible inhibitor of the oxygen-evolving complex of photosynthesis on account of its similar structure to water.
A detonator can easily explode aqueous solutions concentrated above 80% by weight, and even 50% solution might prove detonable if tested in bulk.9780081009710 . ISBN 9780081009710 In air, the combustion is rapid and complete:
At least two factories dealing in hydroxylamine have been destroyed since 1999 with loss of life. Japan Science and Technology Agency Failure Knowledge Database . It is known, however, that ferrous and ferric iron salts accelerate the decomposition of 50% solutions. Hydroxylamine and its derivatives are more safely handled in the form of salts.
It is an irritant to the respiratory tract, skin, eyes, and other mucous membranes. It may be absorbed through the skin, is harmful if swallowed, and is a possible mutagen. MSDS Sigma-Aldrich
|
|
