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Hydroxyproline-derived pseudoenantiomeric [2.2.1] bicyclic phosphines: asymmetric synthesis of (+)- and (-)-pyrrolines.

ABSTRACT: We have prepared two new diastereoisomeric 2-aza-5-phosphabicyclo[2.2.1]heptanes from naturally occurring trans-4-hydroxy-L-proline in six chemical operations. These syntheses are concise and highly efficient, with straightforward purification. When we used these chiral phosphines as catalysts for reactions of γ-substituted allenoates with imines, we obtained enantiomerically enriched pyrrolines in good yields with excellent enantioselectivities. These two diastereoisomeric phosphines functioned as pseudoenantiomers, providing their chiral pyrrolines with opposite absolute configurations.

SUBMITTER: Henry CE

PROVIDER: S-EPMC4151783 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Hydroxyproline-derived pseudoenantiomeric [2.2.1] bicyclic phosphines: asymmetric synthesis of (+)- and (-)-pyrrolines.

Henry Christopher E CE Xu Qihai Q Fan Yi Chiao YC Martin Tioga J TJ Belding Lee L Dudding Travis T Kwon Ohyun O

Journal of the American Chemical Society 20140814 34

We have prepared two new diastereoisomeric 2-aza-5-phosphabicyclo[2.2.1]heptanes from naturally occurring trans-4-hydroxy-L-proline in six chemical operations. These syntheses are concise and highly efficient, with straightforward purification. When we used these chiral phosphines as catalysts for reactions of γ-substituted allenoates with imines, we obtained enantiomerically enriched pyrrolines in good yields with excellent enantioselectivities. These two diastereoisomeric phosphines functioned ...[more]

PMID: 25099350

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