Continuous Flow Ni- or Ru-Zeolite-Catalyzed Intramolecular Dehydration of Diols and Seco-Acids for Macrocyclic Ethers
Dashrat V Sutar1, Akash B Jamdade1, Gourishankar B Swami1
1Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pashan, Pune 411008, India.
Abstract:
Herein, we report the efficient intramolecular dehydrative coupling of symmetrical and unsymmetrical diols for the synthesis of macrocyclic crown ethers in the presence of Ni-zeolite as a catalyst under continuous flow module. This method is also efficient for the intramolecular dehydrative macrolactonization of seco-acids using Ni-zeolite or Ru-zeolite. This flow catalysis is demonstrated by a wide substrate scope with one-time packed Ni-zeolite to produce 20 macrocyclic polyethers and 11 examples of broad macrolactones with water as a byproduct.
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