[5] Hydroxylamine was first prepared as hydroxylammonium chloride in 1865 by the German chemist Wilhelm Clemens Lossen (1838-1906); he reacted tin and hydrochloric acid in the presence of ethyl nitrate.
[11] Another route to NH2OH is the Raschig process: aqueous ammonium nitrite is reduced by HSO−3 and SO2 at 0 °C to yield a hydroxylamido-N,N-disulfonate anion: This ammonium hydroxylamine disulfonate anion is then hydrolyzed to give hydroxylammonium sulfate: Julius Tafel discovered that hydroxylamine hydrochloride or sulfate salts can be produced by electrolytic reduction of nitric acid with HCl or H2SO4 respectively:[12][13] Hydroxylamine can also be produced by the reduction of nitrous acid or potassium nitrite with bisulfite: Hydrochloric acid disproportionates nitromethane to hydroxylamine hydrochloride and carbon monoxide via the hydroxamic acid.
[citation needed] A direct lab synthesis of hydroxylamine from molecular nitrogen in water plasma was demonstrated in 2024.
Similarly to amines, one can distinguish hydroxylamines by their degree of substitution: primary, secondary and tertiary.
The hydrolysis of N-substituted oximes, hydroxamic acids, and nitrones easily provides hydroxylamines.
High concentrations of hydroxylamine are used by biologists to introduce mutations by acting as a DNA nucleobase amine-hydroxylating agent.
[23] 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.
[24] 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.
[25] 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,[26] and mutation of purified DNA in vitro.
[27] An alternative industrial synthesis of paracetamol developed by Hoechst–Celanese involves the conversion of ketone to a ketoxime with hydroxylamine.
[30] Cytochrome P460, an enzyme found in the ammonia-oxidizing bacteria Nitrosomonas europea, can convert hydroxylamine to nitrous oxide, a potent greenhouse gas.
It is used as an irreversible inhibitor of the oxygen-evolving complex of photosynthesis on account of its similar structure to water.