Superacid-promoted synthesis of indolizidine derivatives

TETRAHEDRON LETTERS

卷:59

Article

Kennedy, Sean¹  Kethe, Anila¹  Qarah, Ahmad¹  Klumpp, Douglas A.¹ 

[1] Northern Illinois Univ, Dept Chem & Biochem, De Kalb, IL 60115 USA

关键词: Heterocycles;    Alkaloid;    Superacid;    Electrocyclization;    Acyliminium ions;   

DOI  :  10.1016/j.tetlet.2018.03.094

来源: Elsevier

【 摘 要 】

A series of amido-acetals were reacted with the Brensted superacid, CF3SO3H, to provides indolizidine derives by a cyclization cascade. A mechanism is proposed involving formation of a vinylogous enol which undergoes a 6 pi-electrocyclization reaction with an adjacent N-acyl iminium ion group. With aryl substituents, there is a strong tendency for the N-acyl iminium ion group to undergo Friedel-Crafts type cyclizations with the aryl group. The synthetic methodology was used to prepare the alkaloid natural product, ipalbidine. (C) 2018 Elsevier Ltd. All rights reserved.

【 授权许可】

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