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A convenient, general synthesis of 1,1-dimethylallyl esters as protecting groups for carboxylic acids.

ABSTRACT: [reaction: see text] Carboxylic acids were converted in high yield to their 1,1-dimethylallyl (DMA) esters in two steps. Palladium-catalyzed deprotection of DMA esters was shown to be compatible with tert-butyl, benzyl, and Fmoc protecting groups, and Fmoc deprotection could be carried out selectively in the presence of DMA esters. DMA esters were also shown to be resistant to nucleophilic attack, suggesting that they will serve as alternatives to tert-butyl esters when acidic deprotection conditions need to be avoided.

SUBMITTER: Sedighi M

PROVIDER: S-EPMC1482401 | biostudies-other | 2005 Apr

REPOSITORIES: biostudies-other

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A convenient, general synthesis of 1,1-dimethylallyl esters as protecting groups for carboxylic acids.

Sedighi Minoo M Lipton Mark A MA

Organic letters 20050401 8

[reaction: see text] Carboxylic acids were converted in high yield to their 1,1-dimethylallyl (DMA) esters in two steps. Palladium-catalyzed deprotection of DMA esters was shown to be compatible with tert-butyl, benzyl, and Fmoc protecting groups, and Fmoc deprotection could be carried out selectively in the presence of DMA esters. DMA esters were also shown to be resistant to nucleophilic attack, suggesting that they will serve as alternatives to tert-butyl esters when acidic deprotection condi ...[more]

PMID: 15816730

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