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Current Organic Chemistry

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ISSN (Print): 1385-2728
ISSN (Online): 1875-5348

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Research Article

Decarboxylative Propargylation/Hydroamination/Aromatization Enabled by Copper/ Amine Cooperative Catalysis: Construction of Cyclopenta[b]indole Derivatives

Author(s): Jiale Xiong, Xiaoyun Zhao, Xing Feng and Jiang Xianxing*

Volume 24, Issue 12, 2020

Page: [1384 - 1395] Pages: 12

DOI: 10.2174/1385272824999200701115141

Price: $65

Abstract

An efficient decarboxylative cycloaddition of 2,3-dioxopyrrolidines and ethynyl benzoxazinanones has been established by cooperative copper/amine catalysis. A copper– allenylidene complex and enolate intermediate, each catalytically generated from distinct substrates, underwent a cascade propargylation/hydroamination/aromatization process to construct a big library of cyclopenta[b]indole derivatives with good to excellent yields and excellent diastereoselectivity.

Keywords: Cooperative catalysis, cascade reaction, cyclopenta[b]indole, ethynyl benzoxazinanone, 2, 3-dioxopyrrolidine, copper– allenylidene.

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