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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Click annulation of pseudo[2]rotaxane to [2]catenane exploiting homoditopic nitrile N-oxide
Tatsuya Yuki1, Yasuhito Koyama, Tohru Matsumura
1Department of Organic and Polymeric Materials, Tokyo Institute of Technology, 2-12-1 (H-126), Ookayama, Meguro, Tokyo 152-8552, Japan.
Abstract:
A mild annulation reaction of a propargyl-terminated pseudorotaxane with a homoditopic stable nitrile N-oxide enabled the efficient synthesis of catenanes consisting of not only dibenzo-24-crown-8-ether (DB24C8) but also dibenzo-30-crown-10-ether (DB30C10) as a wheel component. A dynamic (1)H NMR study showed the highly enhanced mobility of the components of the DB30C10-based [2]catenane due to the enlarged wheel cavity.
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