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Generating Stereodiversity: Diastereoselective Fluorination and Highly Diastereoselective Epimerization of α-Amino Acid Building Blocks.

ABSTRACT: Diastereoselective fluorination of N-Boc ( R)- and ( S)-2,2-dimethyl-4-((arylsulfonyl)methyl)oxazolidines and a previously unknown diastereoselective epimerization at the fluorine-bearing carbon atom α to the sulfone was realized. Diastereoselectivities of both reactions were excellent for benzothiazolyl sulfones, allowing access to two enantiomerically pure diastereomers from one chiral precursor. To demonstrate synthetic utility, the benzothiazolyl sulfones were converted to diastereomerically pure ( S, S)- and ( R, S)-benzyl sulfones via sulfinate salts and to amino acids. To understand the diastereoselectivities, DFT analysis was performed.

SUBMITTER: Wei W

PROVIDER: S-EPMC8117975 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Generating Stereodiversity: Diastereoselective Fluorination and Highly Diastereoselective Epimerization of α-Amino Acid Building Blocks.

Wei Wei W Khangarot Rama Kanwar RK Stahl Lothar L Veresmortean Cristina C Pradhan Padmanava P Yang Lijia L Zajc Barbara B

Organic letters 20180601 12

Diastereoselective fluorination of N-Boc ( R)- and ( S)-2,2-dimethyl-4-((arylsulfonyl)methyl)oxazolidines and a previously unknown diastereoselective epimerization at the fluorine-bearing carbon atom α to the sulfone was realized. Diastereoselectivities of both reactions were excellent for benzothiazolyl sulfones, allowing access to two enantiomerically pure diastereomers from one chiral precursor. To demonstrate synthetic utility, the benzothiazolyl sulfones were converted to diastereomerically ...[more]

PMID: 29856640

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