|
The Curtius rearrangement (or Curtius reaction or Curtius degradation), as first defined by Theodor Curtius, is a chemical reaction that involves the rearrangement of an acyl azide to an isocyanate. Several reviews have been published. : The isocyanate can be trapped by a variety of nucleophiles. Water is often added in order to hydrolyze the isocyanate to an amine. When done in the presence of ''tert''-butanol, the reaction generates Boc-protected amines, useful intermediates in organic synthesis. Carboxylic acids 1 can be easily converted to acyl azides 3 using diphenylphosphoryl azide 2. : Likewise, when the Curtius reaction is performed in the presence of benzyl alcohol, Cbz-protected amines are formed. ==Reaction mechanism== The Curtius rearrangement may be thought of as a two-step process, the first step being the loss of nitrogen gas, forming an acyl nitrene (2), and the second step being the rearrangement of acyl nitrenes by migration of R-group to form the desired isocyanate (3). However, current evidence indicates that these two steps are likely concerted (i.e., they occur at the same time), and no free nitrene intermediate is formed. : 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「Curtius rearrangement」の詳細全文を読む スポンサード リンク
|