Stereoselective Synthesis of Cyclohepta[b]indoles by Visible-Light-Induced [2+2]-Cycloaddition/retro-Mannich-type Reactions.

Angew Chem Int Ed Engl

State Key Laboratory of Chemical Oncogenomics and Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055, P. R. China.

Published: May 2021


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Article Abstract

A novel method for the concise synthesis of cyclohepta[b]indoles in high yields was developed. The method involves a visible-light-induced, photocatalyzed [2+2]-cycloaddition/ retro-Mannich-type reaction of enaminones. Experimental and computational studies suggested that the reaction is a photoredox process initiated by single-electron oxidation of an enaminone moiety, which undergoes subsequent cyclobutane formation and rapidly fragmentation in a radical-cation state to form cyclohepta[b]indoles.

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http://dx.doi.org/10.1002/anie.202101104DOI Listing

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