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Catalytic Enantioselective Synthesis of Guvacine Derivatives through [4 + 2] Annulations of Imines with ?-Methylallenoates.

ABSTRACT: P-Chiral [2.2.1] bicyclic phosphines (HypPhos catalysts) have been applied to reactions between ?-alkylallenoates and imines, producing guvacine derivatives. These HypPhos catalysts were assembled from trans-4-hydroxyproline, with the modular nature of the synthesis allowing variations of the exocyclic P and N substituents. Among them, exo-( p-anisyl)-HypPhos was most efficacious for [4 + 2] annulations between ethyl ?-methylallenoate and imines. Through this method, ( R)-aplexone was identified as being responsible for the decrease in the cellular levels of cholesterol.

SUBMITTER: Xu Q

PROVIDER: S-EPMC6173629 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Catalytic Enantioselective Synthesis of Guvacine Derivatives through [4 + 2] Annulations of Imines with α-Methylallenoates.

Xu Qihai Q Dupper Nathan J NJ Smaligo Andrew J AJ Fan Yi Chiao YC Cai Lingchao L Wang Zhiming Z Langenbacher Adam D AD Chen Jau-Nian JN Kwon Ohyun O

Organic letters 20180924 19

P-Chiral [2.2.1] bicyclic phosphines (HypPhos catalysts) have been applied to reactions between α-alkylallenoates and imines, producing guvacine derivatives. These HypPhos catalysts were assembled from trans-4-hydroxyproline, with the modular nature of the synthesis allowing variations of the exocyclic P and N substituents. Among them, exo-( p-anisyl)-HypPhos was most efficacious for [4 + 2] annulations between ethyl α-methylallenoate and imines. Through this method, ( R)-aplexone was identified ...[more]

PMID: 30246538

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