Reactions
- Pyrolytic elimination. Amine oxides, when heated to 150 to 200 °C eliminate a hydroxylamine, resulting in an alkene. This pyrolytic syn-elimination reaction is known under the name Cope reaction. The mechanism is similar to that of the Hofmann elimination.
- Reduction to amines. Amine oxides are readily converted to the parent amine by common reduction reagents including lithium aluminium hydride, sodium borohydride, catalytic reduction, zinc / acetic acid, and iron / acetic acid. Pyridine N-oxides can be deoxygenated by phosphorus oxychloride
- Sacrificial catalysis. Oxidants can be regenerated by reduction of N-oxides, as in the case of regeneration of osmium tetroxide by N-methylmorpholine oxide.
- O-alkylation. Pyridine N-oxides react with alkyl halides to the O-alkylated product
- In the Meisenheimer rearrangement (after Jakob Meisenheimer) certain N-oxides R1R2R3N+O- rearrange to hydroxylamines R2R3N-O-R1
- in a 1,2-rearrangement:
- or a 2,3-rearrangment:
- In the Polonovski reaction a tertiary N-oxide is cleaved by acetic acid anhydride to the corresponding acetamide and aldehyde:
Read more about this topic: Amine Oxides
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