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The Gomberg–Bachmann reaction, named for the Ukrainian-American chemist Moses Gomberg and the American chemist Werner Emmanuel Bachmann, is an aryl-aryl coupling reaction via a diazonium salt.〔W. Pötsch. ''Lexikon bedeutender Chemiker'' (VEB Bibliographisches Institut Leipzig, 1989) (ISBN 3817110553)〕〔M. B. Smith, J. March. ''March's Advanced Organic Chemistry'' (Wiley, 2001) (ISBN 0-471-58589-0)〕 : The arene compound 1 (here benzene) is coupled with base with the diazonium salt 2 to the biaryl 3 through an intermediate aryl radical. For example, p-bromobiphenyl may be prepared from 4-bromoaniline and benzene: : BrC6H4NH2 + C6H6 → BrC6H4−C6H5 The reaction offers a wide scope for both diazonium component and arene component but yields are generally low following the original procedure (less than 40%), given the many side-reactions of diazonium salts. Several improvements have been suggested. One possibility is to employ diazonium tetrafluoroborates in arene solvent together with a phase-transfer catalyst, another is to use 1-aryl-3,3-dialkyltriazenes. ==Pschorr reaction== One intramolecular variation which gives better results is the Pschorr reaction:〔''Review Article'', Kenneth K. Laali and Mohammadreza Shokouhimehr, The Pschorr Reaction, a Fresh Look at a Classical Transformation Current Organic Synthesis, 2009, 6, 193–202. 〕 : The group Z can be CH2, CH2CH2, NH and CO (to fluorenone ) to name just a few. 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「Gomberg–Bachmann reaction」の詳細全文を読む スポンサード リンク
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