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This study shows that alpha-diazoketones efficiently undergo Wolff rearrangement under blue LED light, achieving near 100% quantum yield. This photoreactivity enables selective multicomponent reactions for diverse molecule synthesis.

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Area of Science:

  • Organic Chemistry
  • Photochemistry

Background:

  • Diazoketones are versatile organic compounds.
  • Photochemical reactions offer selective synthesis pathways.

Purpose of the Study:

  • To investigate the photophysical properties and photoreactivity of diazoketones under blue LED irradiation.
  • To explore the Wolff rearrangement and subsequent multicomponent reactions of diazoketones.

Main Methods:

  • Irradiation of variously substituted diazoketones using blue LED light.
  • Analysis of photophysical properties and quantum yields.
  • Conducting multicomponent reactions in the presence of isocyanides and carboxylic acids/silanols.
  • Utilizing both batch and continuous flow processes.

Main Results:

  • Alpha-diazoketones exhibit highly efficient Wolff rearrangement under blue LED light, with quantum yields near 100%.
  • The photoreactivity is structure-independent and highly selective, minimizing side reactions.
  • Multicomponent reactions with isocyanides and carboxylic acids/silanols yield alpha-acyloxy- and alpha-silyloxyacrylamides with improved scope and selectivity.
  • The reactions are effective in both batch and continuous flow.

Conclusions:

  • Blue LED irradiation provides a highly efficient and selective method for diazoketone Wolff rearrangement.
  • This photochemical approach enables diverse molecule synthesis through coupled multicomponent reactions.
  • The methodology offers a valuable tool for organic synthesis with potential for further expansion.