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Iridium-catalyzed hydrocarboxylation of 1,1-dimethylallene: byproduct-free reverse prenylation of carboxylic acids.

ABSTRACT: Exposure of carboxylic acids 1a-12a to commercially available 1,1-dimethylallene in the presence of substoichiometric quantities of an iridium catalyst prepared in situ from [Ir(cod)Cl]2 and BIPHEP provides the corresponding 1,1-dimethylallyl (reverse prenyl) esters 1b-12b in 74-92% isolated yield. This protocol represents the first branch-regioselective allene hydrocarboxylation. Stoichiometric byproducts are not generated in this process and protecting groups are not required for alcohols, phenols, and indolic amines.

SUBMITTER: Kim IS

PROVIDER: S-EPMC2868924 | biostudies-literature | 2008 Feb

REPOSITORIES: biostudies-literature

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Iridium-catalyzed hydrocarboxylation of 1,1-dimethylallene: byproduct-free reverse prenylation of carboxylic acids.

Kim In Su IS Krische Michael J MJ

Organic letters 20080109 3

Exposure of carboxylic acids 1a-12a to commercially available 1,1-dimethylallene in the presence of substoichiometric quantities of an iridium catalyst prepared in situ from [Ir(cod)Cl]2 and BIPHEP provides the corresponding 1,1-dimethylallyl (reverse prenyl) esters 1b-12b in 74-92% isolated yield. This protocol represents the first branch-regioselective allene hydrocarboxylation. Stoichiometric byproducts are not generated in this process and protecting groups are not required for alcohols, phe ...[more]

PMID: 18181640

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