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The Hofmann rearrangement is the organic reaction of a primary amide to a primary amine with one fewer carbon atoms.〔McMurry, J. ''Organic Chemistry, 5th edition〕 The reaction is named after its discoverer - August Wilhelm von Hofmann. This reaction is also sometimes called the Hofmann degradation or the Harmon Process, and should not be confused with the Hofmann elimination. ==Mechanism== The reaction of bromine with sodium hydroxide forms sodium hypobromite ''in situ'', which transforms the primary amide into an intermediate isocyanate via a formation of a nitrene. The intermediate isocyanate is hydrolyzed to a primary amine, giving off carbon dioxide. 〔 #Base abstracts an acidic N-H proton, yielding an anion. #The anion reacts with bromine in an α-substitution reaction to give an ''N''-bromoamide. #Base abstraction of the remaining amide proton gives a bromoamide anion. #The bromoamide anion rearranges as the R group attached to the carbonyl carbon migrates to nitrogen at the same time the bromide ion leaves, giving an isocyanate. #The isocyanate adds water in a nucleophilic addition step to yield a carbamic acid (aka urethane). #The carbamic acid spontaneously loses CO2, yielding the amine product. 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「Hofmann rearrangement」の詳細全文を読む スポンサード リンク
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