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Synlett 2005(18): 2808-2810
DOI: 10.1055/s-2005-918916
DOI: 10.1055/s-2005-918916
LETTER
© Georg Thieme Verlag Stuttgart · New York
Selective Tetrahydropyranylation under Non-Acidic Conditions
Further Information
Received
30 June 2005
Publication Date:
10 October 2005 (online)
Publication History
Publication Date:
10 October 2005 (online)
Abstract
We report that the tetrahydropyranylation of hydroxyl groups, exhibiting especially very low nucleophilicities, can be achieved by means of Mitsunobu reaction with 2-hydroxytetrahydropyran. This reaction led to the protection of phenols and pyridinols without the use of an acidic catalyst. For instance hydroxypyridines could not be protected by dihydropyran under acidic conditions, whereas they underwent a smooth tetrahydropyranylation under Mitsunobu conditions. The method is selective for a phenol over an alcohol.
Key words
protecting groups - glycosylations - acetals - phenols - pyridines
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1a
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