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Lewis-Acid-Catalyzed (3+2) Annulation of 2-Indolylmethanols with Propargylic Alcohols to Access Cyclopenta[b]indoles.

ABSTRACT: Herein, a Sc(OTf)₃-catalyzed (3+2) annulation of 2-indolylmethanols with propargylic alcohols is reported. The reaction proceeds via a Friedel-Crafts-type allenylation/5-exo-annulation cascade. In the reaction, 2-indolylmethanol is used as a three-carbon synthon, and propargyl alcohol is used as a two-carbon synthon. This method provides a direct and high-yield pathway for synthetically useful cyclopenta[b]indoles. In general, the method features easily accessible substrates with broad scope and generality, the formation of multiple bonds with high efficiency, and easy scale-up.

SUBMITTER: Wu TF

PROVIDER: S-EPMC10974089 | biostudies-literature | 2024 Mar

REPOSITORIES: biostudies-literature

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Lewis-Acid-Catalyzed (3+2) Annulation of 2-Indolylmethanols with Propargylic Alcohols to Access Cyclopenta[b]indoles.

Wu Teng-Fei TF Fu Zhao-Jie ZJ Zhang Yi-Rui YR Qiu Zong-Wang ZW Li Bao Qiong BQ Chen Shao-Shuai SS Pan Han-Peng HP Ma Ai-Jun AJ Zhang Xiang-Zhi XZ

Molecules (Basel, Switzerland) 20240312 6

Herein, a Sc(OTf)3-catalyzed (3+2) annulation of 2-indolylmethanols with propargylic alcohols is reported. The reaction proceeds via a Friedel-Crafts-type allenylation/5-exo-annulation cascade. In the reaction, 2-indolylmethanol is used as a three-carbon synthon, and propargyl alcohol is used as a two-carbon synthon. This method provides a direct and high-yield pathway for synthetically useful cyclopenta[b]indoles. In general, the method features easily accessible substrates wi ...[more]

PMID: 38542887

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