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The 4-(tert-butyldiphenylsiloxy)-3-fluorobenzyl group: a new alcohol protecting group, fully orthogonal with the p-methoxybenzyl group and removable under desilylation conditions.

ABSTRACT: A new benzyl ether-type protecting group for alcohols, the 4-(tert-butyldiphenylsiloxy)-3-fluorobenzyl group, is introduced. The protecting group is introduced by means of the readily prepared benzyl bromide and is cleaved with tetrabutylammonium fluoride in dimethylformamide under microwave irradiation. The fluoride substituent provides stability to oxidizing conditions, such that the new protecting group is fully compatible with the removal of p-methoxybenzyl ethers with DDQ. Applications of the new protecting group in the direct stereocontrolled synthesis of beta-mannopyranosides are presented.

SUBMITTER: Crich D

PROVIDER: S-EPMC3102264 | biostudies-literature | 2009 Mar

REPOSITORIES: biostudies-literature

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The 4-(tert-butyldiphenylsiloxy)-3-fluorobenzyl group: a new alcohol protecting group, fully orthogonal with the p-methoxybenzyl group and removable under desilylation conditions.

Crich David D Li Linfeng L Shirai Michio M

The Journal of organic chemistry 20090301 6

A new benzyl ether-type protecting group for alcohols, the 4-(tert-butyldiphenylsiloxy)-3-fluorobenzyl group, is introduced. The protecting group is introduced by means of the readily prepared benzyl bromide and is cleaved with tetrabutylammonium fluoride in dimethylformamide under microwave irradiation. The fluoride substituent provides stability to oxidizing conditions, such that the new protecting group is fully compatible with the removal of p-methoxybenzyl ethers with DDQ. Applications of t ...[more]

PMID: 19243158

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