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Highly stereoselective gram scale synthesis of all the four diastereoisomers of Boc-protected 4-methylproline carboxylates.

ABSTRACT: A general and practical synthetic process for all the four diastereoisomers of Boc-protected 4-methylproline carboxylates has been developed with essentially complete stereoselectivity on the gram scale, which represents the most diastereoselective preparation of 4-methylproline derivatives to date. This synthesis features an Evans asymmetric alkylation to elegantly establish the challenging stereochemistry of the 4-methyl group, providing valuable insights for the diastereoselective preparation of 4-substituted prolines.

SUBMITTER: Sun K

PROVIDER: S-EPMC9072942 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Highly stereoselective gram scale synthesis of all the four diastereoisomers of Boc-protected 4-methylproline carboxylates.

Sun Kehuan K Tao Cheng C Long Bohua B Zeng Xiaobin X Wu Zhengzhi Z Zhang Ronghua R

RSC advances 20191008 55

A general and practical synthetic process for all the four diastereoisomers of Boc-protected 4-methylproline carboxylates has been developed with essentially complete stereoselectivity on the gram scale, which represents the most diastereoselective preparation of 4-methylproline derivatives to date. This synthesis features an Evans asymmetric alkylation to elegantly establish the challenging stereochemistry of the 4-methyl group, providing valuable insights for the diastereoselective preparation ...[more]

PMID: 35530808

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