Copper Catalyzed [3+2] Annulation Reaction of Exocyclic Sulfonyl Enamides for the Synthesis of N,O-Spiroketal and Spiroketal.

Chemistry

Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, Department of Chemistry, East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China.

Published: August 2024


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Article Abstract

A copper-catalyzed [3+2] annulation reaction of exocyclic enamines/enol ethers with 1,4-benzoquinone esters has been developed, providing facile access to N,O-spiroketals and spiroketals under mild conditions with broad substrate scope (26 examples, 71-94 % yields). Gram scale synthesis and chemical transformations demonstrated that this method is potentially useful in the synthesis of natural products and drugs containing a N,O- spiroketal moiety. The chiral N,O-spiroketal could be obtained with 98 % ee after recrystallization, when a chiral SaBOX ligand was employed.

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http://dx.doi.org/10.1002/chem.202401062DOI Listing

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