Wheel of Ketenes Reactions

Most of us like kittens, how about the 'cute' ketenes? 😻


The Wolff rearrangement ([1,2]-rearrangement of an α-diazoketone to a ketene via a carbene, catalyzed by light, heat or transition metals) is part of the Arndt–Eistert synthesis aka the Arndt–Eistert reaction (or homologation). The ketenes can either be captured by a variety of nucleophiles or undergo Staudinger [2 + 2] cycloaddition including dimerization. A ketene is, therefore, an important intermediate to making a variety of organics.



Wheel of ketenes reactions: Click/tap to enlarge the image


Substrates (on the infographic):

  1. Ethenone
  2. Carboxylic acids
  3. Thiols
  4. Secondary amines
  5. Alcohols
  6. Water
  7. Nucleophiles
  8. Imines (-> Î²-lactam)

What other wheel(s) 🎡 of organic reactions would you like to see❓ Questions❓ Let Chemaficionado know in the comments below or at mychemistryhomework@gmail.com❗


Reference:

Valiulin, R. Organic Chemistry: 100 Must-Know Mechanisms; De Gruyter: Berlin, 2023.

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