Metal‐Free Dehydrogenative Diels–Alder Reactions of 2‐Methyl‐3‐Alkylindoles with Dienophiles: Rapid Access to Tetrahydrocarbazoles, Carbazoles, and Heteroacenes
Angewandte Chemie International EditionPublished 10 June 2015
Liejin Zhou, Bing Xu, Junliang Zhang
Citations87
SJR quartileQ1
SJR score5.55
SNIP2.47
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TL;DR
An unprecedented strategy for in situ generation of indole-based ortho-quinodimethanes from 2-methyl-3-alkylmethylindoles by either a metal-free DDQ- or BQ-mediated dehydrogenative process was developed.
Abstract
An unprecedented strategy for in situ generation of indole-based ortho-quinodimethanes (oQDMs) from 2-methyl-3-alkylmethylindoles by either a metal-free DDQ- or BQ-mediated dehydrogenative process was developed. These oQDMs were trapped by electron-deficient dienophiles to provide a facile approach to synthetically valuable tetrahydrocarbazoles, carbazoles, and hetereoacenes. The salient features of this transformation include direct C(sp(3))-H bond functionalizations, readily available starting materials, metal-free conditions, high efficiency, operational simplicity, and ease of scale-up.
Keywords
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