Rearrangement amine oxides, tertiary

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

Sigmatropic Rearrangements of Tertiary Amine Oxides (The Meisenheimer Rearrangement)... 

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

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.)... 

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

Meisenheimer rearrangement The rearrangement of a tertiary amine oxide on heating to give a substituted hydroxylamine. The migrating group is usually allylic or benzylic. 

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

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... 

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). 

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

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... 

SCHEME 3.34 Meisenheimer rearrangement of tertiary amine oxides. 

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 ... 

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 ... 

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