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An improved method for the protection of carboxylic acids as 1,1-dimethylallyl esters.

ABSTRACT: 1,1-Dimethylallyl (DMA) esters of various N-protected amino acids have been synthesized using prenyldimethylsulfonium tetrafluroborate, a reagent that can be readily made and stored, in conjunction with catalytic CuBr. These reactions were complete within several hours and afforded DMA esters in high yields. As has been previously shown in our group, DMA esters represent a palladium-labile proctecting group for carboxylic acids that resists nucleophilic attack as a tert-butyl ester would.

SUBMITTER: Sedighi M

PROVIDER: S-EPMC2582559 | biostudies-literature | 2006 Dec

REPOSITORIES: biostudies-literature

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An improved method for the protection of carboxylic acids as 1,1-dimethylallyl esters.

Sedighi Minoo M Calimsiz Selçuk S Lipton Mark A MA

The Journal of organic chemistry 20061201 25

1,1-Dimethylallyl (DMA) esters of various N-protected amino acids have been synthesized using prenyldimethylsulfonium tetrafluroborate, a reagent that can be readily made and stored, in conjunction with catalytic CuBr. These reactions were complete within several hours and afforded DMA esters in high yields. As has been previously shown in our group, DMA esters represent a palladium-labile proctecting group for carboxylic acids that resists nucleophilic attack as a tert-butyl ester would. ...[more]

PMID: 17137386

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