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Nazarov cyclization of 1,4-pentadien-3-ols: preparation of cyclopenta[b]indoles and spiro[indene-1,4'-quinoline]s.

ABSTRACT: The first Lewis acid-catalyzed intramolecular interrupted Nazarov cyclization of 1,4-pentadien-3-ols is described. Using FeBr3 as the catalyst, a series of new substituted cyclopenta[b]indoles was prepared-through a sequence of Nazarov cyclization, nucleophilic amination, and isomerization-with good yields and high diastereo- and regioselectivities. A similar catalytic process was also developed for the synthesis of structurally interesting spiro[indene-1,4'-quinoline]s.

SUBMITTER: Wang Z

PROVIDER: S-EPMC5560599 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Nazarov cyclization of 1,4-pentadien-3-ols: preparation of cyclopenta[b]indoles and spiro[indene-1,4'-quinoline]s.

Wang Zhiming Z Xu Xingzhu X Gu Zhanshou Z Feng Wei W Qian Houjun H Li Zhengyi Z Sun Xiaoqiang X Kwon Ohyun O

Chemical communications (Cambridge, England) 20160201 13

The first Lewis acid-catalyzed intramolecular interrupted Nazarov cyclization of 1,4-pentadien-3-ols is described. Using FeBr3 as the catalyst, a series of new substituted cyclopenta[b]indoles was prepared-through a sequence of Nazarov cyclization, nucleophilic amination, and isomerization-with good yields and high diastereo- and regioselectivities. A similar catalytic process was also developed for the synthesis of structurally interesting spiro[indene-1,4'-quinoline]s. ...[more]

PMID: 26771024

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