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In the reaction, thermal or photochemical decomposition of N-halogenated amine 1 in the presence of a strong acid (concentrated sulfuric acid or concentrated CF 3 CO 2 H) generates a nitrogen radical intermediate. The radical then abstracts an intramolecular hydrogen atom to give a cyclic amine 2 (pyrrolidine or, in some cases, piperidine).
However, there also have been reported examples of base-free Stieglitz rearrangements of N-halogenated amines. An example for that can be found in the total synthesis of (±)-lycopodine by Paul Grieco et al. [6] [29] There, a ring formation takes place by a rearrangement on a secondary haloamine by subjecting it to silver tetrafluoroborate. [6]
Because primary and secondary amines react with aldehydes and ketones, the most common variety of these aminocarbonyl compounds feature tertiary amines. Such compounds are produced by amination of α-haloketones and α-haloaldehydes. [1] Examples include cathinones, methadone, molindone, pimeclone, ferruginine, and tropinone.
In chemistry, halogenation is a chemical reaction which introduces one or more halogens into a chemical compound. Halide-containing compounds are pervasive, making this type of transformation important, e.g. in the production of polymers, drugs. [1]
For example, reaction of 1-bromooctane with ammonia yields almost equal amounts of the primary amine and the secondary amine. [3] Therefore, for laboratory purposes, N-alkylation is often limited to the synthesis of tertiary amines. An exception is the amination of alpha-halo carboxylic acids that do permit synthesis of primary amines with ...
By reaction with tertiary amines, long-chain alkyl bromides such as 1-bromododecane, give quaternary ammonium salts, which are used as phase transfer catalysts. [ 9 ] With Michael acceptors the addition is also anti-Markovnikov because now a nucleophilic X − reacts in a nucleophilic conjugate addition for example in the reaction of HCl with ...
In the Mannich reaction, primary or secondary amines or ammonia react with formaldehyde to form a Schiff base. Tertiary amines lack an N–H proton and so do not react. The Schiff base can react with α-CH-acidic compounds (nucleophiles) that include carbonyl compounds, nitriles, acetylenes, aliphatic nitro compounds, α-alkyl-pyridines or imines.
Mixed ether-amine ligands. Another large class of macrocyclic ligands feature both ether and amines.. [8] One example is the diaza-18-crown-6, [(CH 2 CH 2 O) 2 (CH 2 CH 2 NH)] 2. [9] Lariate crowns. The presence of the amine allows the formation of Lariat crown ethers, which feature sidearms that augment complexation of cation. [10]