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Amine alkylation (amino-de-halogenation) is a type of organic reaction between an alkyl halide and ammonia or an amine. The reaction is called nucleophilic aliphatic substitution (of the halide), and the reaction product is a higher substituted amine. The method is widely used in the laboratory, but is less important industrially, where alkyl halides are not preferred alkylating agents. :Alkylation of an amine When the amine is a tertiary amine the reaction product is a quaternary ammonium salt in the Menshutkin reaction: :Alkylation of a tertiary amine Amines and ammonia are generally sufficiently basic to undergo direct alkylation, often under mild conditions. The reactions are difficult to control because the reaction product (a primary amine or a secondary amine) are often more nucleophilic than the precursor and will thus preferentially react with the alkylating agent. For example, reaction of 1-bromooctane with ammonia yields almost equal amounts of the primary amine and the secondary amine.〔''Organic Chemistry'' John McMurry 2nd Ed.〕 Therefore, for laboratory purposes, N-alkylation is often limited to the synthesis of tertiary amines. A notable exception is the reactivity of alpha-halo carboxylic acids that do permit synthesis of primary amines with ammonia.〔Organic Syntheses, Coll. Vol. 1, p.48 (1941); Vol. 4, p.3 (1925). (Link )〕 Intramolecular reactions of haloamines X-(CH2)n-NH2 give cyclic aziridines, azetidines and pyrrolidines. ''N''-alkylation is a general and useful route to quaternary ammonium salts from tertiary amines, because overalkylation is not possible. Examples of N-alkylation with alkyl halides are the syntheses of benzylaniline,〔Organic Syntheses, Coll. Vol. 1, p.102 (1941); Vol. 8, p.38 (1928). (Link )〕 1-benzylindole,〔Organic Syntheses, Coll. Vol. 6, p.104 (1988); Vol. 54, p.58 (1974). (Link )〕〔Organic Syntheses, Coll. Vol. 6, p.106 (1988); Vol. 54, p.60 (1974). (Link )〕 and azetidine.〔Organic Syntheses, Coll. Vol. 6, p.75 (1988); Vol. 53, p.13 (1973). (Link )〕 Another example is found in the derivatization of cyclen.〔Org. Synth. 2008, 85, 10-14 (Link )〕 Industrially, ethylenediamine is produced by alkylation of ammonia with 1,2-dichloroethane. ==Aniline and related aryl derivatives== Traditionally, aryl halides (ArX) alkylate amines only reluctantly. The reaction usually requires "activated" aryl halides, such as those with strong electron-withdrawing groups such as nitro groups ortho or para to the halogen atom.〔Organic Chemistry 4th Ed. Morrison & Boyd.〕 For the arylation of amines with unactivated aryl halides, the Buchwald-Hartwig reaction is useful. In this process, palladium complexes serve as catalysts.〔J. F. Hartwig, "Organotransition Metal Chemistry: From Bonding to Catalysis" University Science Books, 2010. ISBN 978-1-891389-53-5.〕 : 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Amine alkylation」の詳細全文を読む スポンサード リンク
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