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Substrate-Controlled Direct α-Stereoselective Synthesis of Deoxyglycosides from Glycals Using B(C6F5)3 as Catalyst.

ABSTRACT: B(C6F5)3 enables the metal-free unprecedented substrate-controlled direct α-stereoselective synthesis of deoxyglycosides from glycals. 2,3-Unsaturated α- O-glycoside products are obtained with deactivated glycals at 75 °C in the presence of the catalyst, while 2-deoxyglycosides are formed using activated glycals that bear no leaving group at C-3 at lower temperatures. The reaction proceeds in good to excellent yields via concomitant borane activation of glycal donor and nucleophile acceptor. The method is exemplified with the synthesis of a series of rare and biologically relevant glycoside analogues.

SUBMITTER: Sau A

PROVIDER: S-EPMC6466476 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Substrate-Controlled Direct α-Stereoselective Synthesis of Deoxyglycosides from Glycals Using B(C6F5)3 as Catalyst.

Sau Abhijit A Palo-Nieto Carlos C Galan M Carmen MC

The Journal of organic chemistry 20190215 5

B(C6F5)3 enables the metal-free unprecedented substrate-controlled direct α-stereoselective synthesis of deoxyglycosides from glycals. 2,3-Unsaturated α- O-glycoside products are obtained with deactivated glycals at 75 °C in the presence of the catalyst, while 2-deoxyglycosides are formed using activated glycals that bear no leaving group at C-3 at lower temperatures. The reaction proceeds in good to excellent yields via concomitant borane activation of glycal do ...[more]

PMID: 30706711

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