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Phosphine-catalyzed [5+1] annulation of ?-sulfonamido-substituted enones with N-sulfonylimines: a facile synthesis of tetrahydropyridines.

ABSTRACT: Phosphine-catalyzed [5+1] annulation of ?-sulfonamido-substituted enones with N-sulfonylimines for the synthesis of 1,2,3,6-tetrahydropyridines is developed. The reaction proceeds smoothly under mild reaction conditions to give the annulation products in moderate to excellent yields. Mechanistic exploration of this new annulation shows that the ?-sulfonamido-substituted enone and the N-sulfonylimine serve as C5 and C1 synthons to furnish the annulation, respectively. Using chiral phosphine as the catalyst, an asymmetric variant of the model reaction gave the chiral product in up to 73% ee.

SUBMITTER: Zhou L

PROVIDER: S-EPMC5892350 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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Phosphine-catalyzed [5+1] annulation of δ-sulfonamido-substituted enones with N-sulfonylimines: a facile synthesis of tetrahydropyridines.

Zhou Leijie L Yuan Chunhao C Zeng Yuan Y Liu Honglei H Wang Chang C Gao Xing X Wang Qijun Q Zhang Cheng C Guo Hongchao H

Chemical science 20180105 7

Phosphine-catalyzed [5+1] annulation of δ-sulfonamido-substituted enones with N-sulfonylimines for the synthesis of 1,2,3,6-tetrahydropyridines is developed. The reaction proceeds smoothly under mild reaction conditions to give the annulation products in moderate to excellent yields. Mechanistic exploration of this new annulation shows that the δ-sulfonamido-substituted enone and the N-sulfonylimine serve as C5 and C1 synthons to furnish the annulation, respectively. Using chiral p ...[more]

PMID: 29675228

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