Enantioselective Total Synthesis of Fortalpinoid Q via a TEMPOBF-Mediated Dehydrative Nazarov Cyclization.

J Am Chem Soc

Department of Chemistry and Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis and Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis and Guangming Advanced Research Institute, Southern University of Science and Technology, Shenzhen 518055, China.

Published: March 2025

The family of diterpenoids represents a captivating class of natural products that are of significant interest from both structural and biological perspectives within our community. Here we wish to report a 15-step, enantioselective total synthesis of the diterpenoid fortalpinoid Q. Our approach highlights (1) a Jacobsen's catalytic enantioselective Claisen rearrangement that enabled the single-step formation of two vicinal stereogenic centers, including an all-carbon quaternary center; (2) a mild, oxoammonium salt (TEMPOBF)-promoted dehydrative Nazarov cyclization that swiftly forged the crucial cyclopentadiene moiety via an unfunctionalized tertiary divinyl carbinol (TDC) substrate; and (3) a facile aldol-lactonization cascade that ultimately resolved the last obstacle in the synthesis.

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http://dx.doi.org/10.1021/jacs.5c00319DOI Listing

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Enantioselective Total Synthesis of Fortalpinoid Q via a TEMPOBF-Mediated Dehydrative Nazarov Cyclization.

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Department of Chemistry and Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis and Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis and Guangming Advanced Research Institute, Southern University of Science and Technology, Shenzhen 518055, China.

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