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Overcoming naphthoquinone deactivation: rhodium-catalyzed C-5 selective C-H iodination as a gateway to functionalized derivatives.

ABSTRACT: We report a Rh-catalyzed method for the C-5 selective C-H iodination of naphthoquinones and show that complementary C-2 selective processes can be achieved under related conditions. C-C bond forming derivatizations of the C-5 iodinated products provide a gateway to previously inaccessible A-ring analogues. The present study encompasses the first catalytic directed ortho-functionalizations of simple (non-bias) naphthoquinones. The strategic considerations outlined here are likely to be applicable to C-H functionalizations of other weakly coordinating and/or redox sensitive substrates.

SUBMITTER: Jardim GAM

PROVIDER: S-EPMC6013821 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Overcoming naphthoquinone deactivation: rhodium-catalyzed C-5 selective C-H iodination as a gateway to functionalized derivatives.

Jardim Guilherme A M GAM da Silva Júnior Eufrânio N EN Bower John F JF

Chemical science 20160302 6

We report a Rh-catalyzed method for the C-5 selective C-H iodination of naphthoquinones and show that complementary C-2 selective processes can be achieved under related conditions. C-C bond forming derivatizations of the C-5 iodinated products provide a gateway to previously inaccessible A-ring analogues. The present study encompasses the first catalytic directed <i>ortho</i>-functionalizations of simple (non-bias) naphthoquinones. The strategic considerations outlined here are likely to be app ...[more]

PMID: 30155019

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