A convenient, general synthesis of 1,1-dimethylallyl esters as protecting groups for carboxylic acids.
A convenient, general synthesis of 1,1-dimethylallyl esters as protecting groups for carboxylic acids.
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DOI：
10.1021/ol0476117
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发表时间：
2005-03
期刊：
影响因子：
5.2
通讯作者：
Minoo Sedighi;M. Lipton
中科院分区：
文献类型：
--
作者：
Minoo Sedighi;M. Lipton
[反应：见正文]羧酸在两步反应中高产率地转化为1，1-二甲基烯丙基(DMA)酯。钯催化的DMA酯脱保护与叔丁基、苄基和Fmoc保护基团相容，在DMA酯存在下Fmoc脱保护可以选择性地进行。DMA酯也被证明可以抵抗亲核攻击，这表明当需要避免酸性去保护条件时，它们将作为叔丁酯的替代品。
[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.