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Hypervalent iodine(III)-promoted intermolecular C-C coupling of vindoline with ?-ketoesters and related substrates.

ABSTRACT: The regioselective intermolecular coupling reaction of vindoline with a wide range of substrates including ?-ketoesters, ?-diketones, ?-ketoaldehydes, ?-ketonitriles, malononitriles, and ?-cyanoesters provides an opportunity for the synthesis of vinblastine analogues containing deep-seated changes in the upper velbanamine subunit. The transition-metal-free hypervalent iodine(III)-promoted intermolecular sp(3)/sp(2) coupling, representing a special class of selective C-H activation with direct carbon-carbon bond formation, proceeds with generation of a quaternary center capable of incorporation of the vinblastine C16' methyl ester and functionalized for subsequent divergent heterocycle introduction.

SUBMITTER: Turner TC

PROVIDER: S-EPMC3607625 | biostudies-literature | 2013 Mar

REPOSITORIES: biostudies-literature

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Hypervalent iodine(III)-promoted intermolecular C-C coupling of vindoline with β-ketoesters and related substrates.

Turner Travis C TC Shibayama Kotaro K Boger Dale L DL

Organic letters 20130219 5

The regioselective intermolecular coupling reaction of vindoline with a wide range of substrates including β-ketoesters, β-diketones, β-ketoaldehydes, β-ketonitriles, malononitriles, and β-cyanoesters provides an opportunity for the synthesis of vinblastine analogues containing deep-seated changes in the upper velbanamine subunit. The transition-metal-free hypervalent iodine(III)-promoted intermolecular sp(3)/sp(2) coupling, representing a special class of selective C-H activation with direct ca ...[more]

PMID: 23421318

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