Copper-Catalyzed Oxygenative Skeletal Rearrangement of Tetrahydro-β-carbolines Using H O and O as Oxygen Sources.

Angew Chem Int Ed Engl

State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Medical University, 550014, Guiyang, P. R. China.

Published: December 2023

Herein, we report an unprecedented skeletal rearrangement reaction of tetrahydro-β-carbolines enabled by copper-catalyzed single-electron oxidative oxygenation, in which H O and O act as oxygen sources to generate a unique 2-hydroxyl-3-peroxide indoline intermediate. The synthetic reactivity of 2-hydroxyl-3-peroxide indoline species was demonstrated by a unique multi-step bond cleavage and formation cascade. Using a readily available copper catalyst under open-air conditions, highly important yet synthetically difficult spiro[pyrrolidone-(3,1-benzoxazine)] products were obtained in a single operation. The synthetic utility of this methodology is demonstrated by the efficient synthesis of the natural products donaxanine and chimonamidine, as well as the 3-hydroxyl-pyrroloindoline scaffold, in just one or two steps.

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http://dx.doi.org/10.1002/anie.202313687DOI Listing

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