Synlett 2017; 28(16): 2189-2193
DOI: 10.1055/s-0036-1588461
letter
© Georg Thieme Verlag Stuttgart · New York

Heat Versus Basic Conditions: Intramolecular Dehydro-Diels–Alder Reaction of 1-Indolyl-1,6-heptadiynes for the Selective Synthesis of Substituted Carbazoles

Takayuki Kudoh
Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan   Email: [email protected]
,
Syo Fujisawa
Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan   Email: [email protected]
,
Megumi Kitamura
Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan   Email: [email protected]
,
Akira Sakakura*
Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan   Email: [email protected]
› Author Affiliations
This project was supported in part by JSPS KAKENHI (26410120)
Further Information

Publication History

Received: 01 May 2017

Accepted after revision: 19 May 2017

Publication Date:
06 July 2017 (online)


Abstract

The intramolecular dehydro-Diels–Alder reaction of 1-indolyl-1,6-heptadiynes proceeds smoothly under rather mild heating conditions to give substituted carbazoles in moderate to good yields. The reaction of 7-aryl-1-indolyl-1,6-heptadiynes under heating gives the corresponding carbazoles chemoselectively in high yields, whereas the reaction under basic conditions gives naphthalenes as major products.

Supporting Information

 
  • References and Notes


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