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Enantioselective para-Claisen Rearrangement for the Synthesis of Illicium-Derived Prenylated Phenylpropanoids.

ABSTRACT: The development of the first enantioselective para-Claisen rearrangement has been achieved. Using a chiral aluminum Lewis acid, illicinole is rearranged to give (-)-illicinone A (er 87:13), which can then be converted into more complex Illicium-derived prenylated phenylpropanoids. The absolute configurations of the natural products (+)-cycloillicinone and (-)-illicarborene A have been determined, and our results cast doubt on the enantiopurity of the natural samples.

SUBMITTER: Homer JA

PROVIDER: S-EPMC8155563 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature

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Enantioselective para-Claisen Rearrangement for the Synthesis of Illicium-Derived Prenylated Phenylpropanoids.

Homer Joshua A JA De Silvestro Irene I Matheson Eilidh J EJ Stuart Jake T JT Lawrence Andrew L AL

Organic letters 20210415 9

The development of the first enantioselective para-Claisen rearrangement has been achieved. Using a chiral aluminum Lewis acid, illicinole is rearranged to give (-)-illicinone A (er 87:13), which can then be converted into more complex Illicium-derived prenylated phenylpropanoids. The absolute configurations of the natural products (+)-cycloillicinone and (-)-illicarborene A have been determined, and our results cast doubt on the enantiopurity of the natural samples. ...[more]

PMID: 33856817

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