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Updated: Feb 28, 2026
Characterizing Lewis Pairs Using Titration Coupled with In Situ Infrared Spectroscopy
Published on: February 20, 2020
Lewis Acid Catalyzed Cyclization Reactions of Ethenetricarboxylates via Intramolecular Hydride Transfer
Shoko Yamazaki1, Taku Naito1, Mamiko Niina1
1Department of Chemistry, Nara University of Education, Department of Chemistry, Nara University of Education , Takabatake-cho, Nara 630-8528, Japan.
Abstract:
Catalytic cyclization of amides of ethenetricarboxylate bearing ether and acetal groups has been examined. The reaction of the amides bearing cyclic ether and acetal groups in the presence of Lewis acid such as Sc(OTf)3 gave spirocyclic piperidine derivatives as major products. The cyclized products may be formed via intramolecular hydride transfer. The reaction mechanism was examined by the DFT calculations. The scope and limitations of the hydride transfer/cyclization reactions of amides of ethenetricarboxylates was investigated, and morpholine formation by intramolecular oxy-Michael addition was also found.
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