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  1. Jan 23, 2023 · The Beckmann rearrangement is a reaction discovered in the mid-1880’s by the chemist Ernst Otto Beckmann. The reaction converts oximes into their corresponding amides 1 allowing the insertion of the nitrogen atom from the C=N bond into the carbon chain forming a C­–N bond. Depending on the starting material, it could also produce nitriles ...

  2. The Beckmann is the rearrangement of the oxime to the amide. This is generally achieved through conversion of the oxime oxygen to a good leaving group, followed by heat, which results in an alkyl (or hydride) shift, breaking the weak N-O bond. The second step involves trapping of the carbon with water (forming an amide) or, if a hydride shift ...

    • Definition: What Is Beckmann rearrangement?
    • Examples of Beckmann Rearrangement
    • Mechanism of Beckmann Rearrangement
    • Applications of Beckmann Rearrangement

    Beckmann rearrangement is an acid-catalyzed reaction of ketoximes into amides. The yield of this reaction increases at elevated temperatures. The reaction is named after German pharmacist and chemist Ernst Otto Beckmann .

    Beckmann rearrangement is used in the conversions of benzophenone oxime to benzanilide and cyclohexanone oxime to caprolactam .

    The mechanism of the Beckmann rearrangement follows the same pattern as a pinacol reaction. The acid converts the oxime OH into a leaving group, and an alkyl group migrates on to the nitrogen as water departs. The product cation is then trapped by water to give an amide .

    In the synthesis of caprolactam, which is used in the production of nylon 6
    For the synthesis of paracetamol by converting a ketone to a ketoxime with the help of hydroxylamine
    In the synthesis of various steroids and drugs
    In the production of some of the chloro bicyclic lactams
  3. C. Ramalingan, Y.-T. Park, J. Org. Chem., 2007, 72, 4536-4538. Zinc (II) catalyzes a single-step protocol for the Beckmann rearrangement using hydroxylamine- O -sulfonic acid (HOSA) as the nitrogen source in water. This environmentally benign and operationally simple method efficiently produces secondary amides under open atmosphere in a pure ...

  4. The Beckmann Rearrangement Alkyl group that migrates does so with retention of configuration, and is always anti to the oxime leaving group N OH N OLVG NH2O H NO Versatile reaction to make lactams and amides Prepared starting from hydroxime, with many leaving groups possible E. Beckmann, Ber. Dtsch. Chem. Ges. 1886, 19, 988.

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  6. Prof. Kevin Shea (Smith College) 3.3: Rearrangements is shared under a CC BY 4.0 license and was authored, remixed, and/or curated by LibreTexts. This chapter focuses on synthetically useful rearrangements including the pinacol, Payne, benzilic acid, Favorskii, Tiffeneau-Demjanov, Wolff, Curtius, Baeyer-Villager, and Beckmann rearrangements.

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