Rearrangement amine oxides, tertiary

Rearrangement of tertiary amine oxides upon treatment with acetic anhydride or acetyl chloride, in which one of the alkyl groups attached to the nitrogen is cleaved, generating the 7V,A/-disubstituted acetamide and aldehyde  

Meisenheimer rearrangement. Rearrangement of tertiary amine oxide to 0,lV,lV-trisubstituted hydroxylamines. 

The thermal rearrangement of tertiary amine oxides, the Meisenheimer rearrangement, generates O, A,A-trisubstituted hydroxylamines. 

Sigmatropic Rearrangements of Tertiary Amine Oxides (The Meisenheimer Rearrangement) 

A study of the mechanism of the rearrangement of a tertiary amine oxide to the 

Sigmatropic rearrangement of allylic tertiary amine-A -oxides to give O-allyl hydroxylamines  

SCHEME 3.34 Meisenheimer rearrangement of tertiary amine oxides. 

MEISENHEIMER N-Oxide Rearrangement Rearrangement of tertiary amine oxides to trisubstituted hydroxylamines via a [2,3] sigmatropic shift. Also chlorination of pyridines via N-oxides (see 1st edition). 

Johnstone, R. A. W. Meisenheimer rearrangement of tertiary amine oxides. Mechanisms of Molecular Migrations 1969, 2, 249-266. 

Formation of O, N, A -trisubstituted hydroxylamines from tertiary amine oxides via [1,2]-R group migration, or [2,3]-sigmatropic rearrangement when R = allyl  

The following reaction mechanism was ruled out by the authors cited [4 + 2] cycloaddition of the diene with the nitrone to give tertiary amine oxide, 7-21, which then thermally rearranges to the product. (Thermal rearrangement of a tertiary amine oxide to an alkylated hydroxylamine is called a Meisenheimer rearrangement.) 

Tert-Amines - sec-amines.1 When a tertiary amine in pyridine is shaken with 2-nitropropane and CuCl under oxygen, it is converted into a nitrosamine (5), which can be isolated in yields of 15-65% and then reduced to a secondary amine. The reaction proceeds through oxidation to an amine oxide (2) with conversion of (1) into 2-nitro-2-propanol (3). This decomposes into acetone and nitrous acid. The nitrous acid traps the secondary amine formed from the amine oxide (2) after rearrangement to the carbinolamine (4). It is noteworthy that even 

Based on these observations. Barker, Monti and Christian (1980) speculated that a high proportion of lAA probably arose as a secondary metabolite resulting from the oxidative deamination of NMT. DMT itself is a poor substrate for MAO (Barlow 1961 Udenfriend et al. 1958). The relative rate of oxidation of NMT is some nine times faster than DMT and 280 times faster than DMT-NO. The TH Cs detected as trace metabolites may be formed from the nonenzymatic condensation of tryptamine and/or NMT with the HCHO formed as an intermediate in the N-demethylation of DMT. Barker, Monti and Christian (1980) have made the interesting observation that direct C-hydroxylation of tertiary amines and tertiary amine N-oxide rearrangement results 

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