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Site-Selective Dehydroxy-Chlorination of Secondary Alcohols in Unprotected Glycosides.

ABSTRACT: To circumvent protecting groups, the site-selective modification of unprotected glycosides is intensively studied. We show that site-selective oxidation, followed by treatment of the corresponding trityl hydrazone with tert-butyl hypochlorite and a H atom donor provides an effective way to introduce a chloride substituent in a variety of mono- and disaccharides. The stereoselectivity can be steered, and a new geminal dichlorination reaction is described as well. This strategy challenges existing methods that lead to overchlorination.

SUBMITTER: Zhang J

PROVIDER: S-EPMC9490796 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature

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Site-Selective Dehydroxy-Chlorination of Secondary Alcohols in Unprotected Glycosides.

Zhang Ji J Reintjens Niels R M NRM Dhineshkumar Jayaraman J Witte Martin D MD Minnaard Adriaan J AJ

Organic letters 20220717 29

To circumvent protecting groups, the site-selective modification of unprotected glycosides is intensively studied. We show that site-selective oxidation, followed by treatment of the corresponding trityl hydrazone with <i>tert-</i>butyl hypochlorite and a H atom donor provides an effective way to introduce a chloride substituent in a variety of mono- and disaccharides. The stereoselectivity can be steered, and a new geminal dichlorination reaction is described as well. This strategy challenges e ...[more]

PMID: 35848103

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