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The Sommelet–Hauser rearrangement (named after M. Sommelet〔M. Sommelet, Compt. Rend. 205, 56 (1937).〕 and Charles R. Hauser〔''Rearrangements of Benzyltrimethylammonium Ion and Related Quaternary Ammonium Ions by Sodium Amide Involving Migration into the Ring'' Simon W. Kantor, Charles R. Hauser J. Am. Chem. Soc., 1951, 73 (9), pp 4122–4131 〕) is a rearrangement reaction of certain benzyl quaternary ammonium salts.〔Organic Syntheses, Coll. Vol. 4, p.585 (1963); Vol. 34, p.61 (1954) (Link ).〕 The reagent is sodium amide or another alkali metal amide and the reaction product a N-dialkyl benzyl amine with a new alkyl group in the aromatic ortho position. :Sommelet-Hauser rearrangement ==Mechanism== The benzylic methylene proton is acidic and deprotonation takes place to produce the benzylic ylide (1). This ylide is in equilibrium with a second ylide that is formed by deprotonation of one of the ammonium methyl groups (2). Though the second ylide is present in much smaller amounts, it undergoes a 2,3-sigmatropic rearrangement and subsequent aromatization to form the final product (3).〔Ahluwalia, V. K., and R. K. Parashar. Organic Reaction Mechanisms. Harrow, U.K.: Alpha Science International, 2005. Print.〕 : The Stevens rearrangement is a competing reaction. 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「Sommelet–Hauser rearrangement」の詳細全文を読む スポンサード リンク
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