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Synthesis of the C(1)-C(13) Fragment of Leiodermatolide via Hydrogen-Mediated C-C Bond Formation.

ABSTRACT: The C(1)-C(13) fragment of the antimitotic marine macrolide leiodermatolide is prepared in seven steps via hydrogenative and transfer-hydrogenative reductive C-C couplings. A hydrogen-mediated reductive coupling of acetylene with a Roche-type aldehyde is used to construct C(7)-C(13). A 2-propanol-mediated reductive coupling of allyl acetate with (E)-2-methylbut-2-enal at a low loading of iridium (1 mol %) is used to construct C(1)-C(6), which is converted to an allylsilane using Oestereich's copper-catalyzed allylic substitution of Si-Zn reagents. The union of the C(1)-C(6) and C(7)-C(13) fragments is achieved via stereoselective Sakurai allylation.

SUBMITTER: Roane J

PROVIDER: S-EPMC5732063 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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Synthesis of the C(1)-C(13) Fragment of Leiodermatolide via Hydrogen-Mediated C-C Bond Formation.

Roane James J Wippich Julian J Ramgren Stephen D SD Krische Michael J MJ

Organic letters 20171123 24

The C(1)-C(13) fragment of the antimitotic marine macrolide leiodermatolide is prepared in seven steps via hydrogenative and transfer-hydrogenative reductive C-C couplings. A hydrogen-mediated reductive coupling of acetylene with a Roche-type aldehyde is used to construct C(7)-C(13). A 2-propanol-mediated reductive coupling of allyl acetate with (E)-2-methylbut-2-enal at a low loading of iridium (1 mol %) is used to construct C(1)-C(6), which is converted to an allylsilane using Oestereich's cop ...[more]

PMID: 29168383

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