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Synthesis of diverse indole libraries on polystyrene resin - Scope and limitations of an organometallic reaction on solid supports.

ABSTRACT: The synthesis of diverse substituted indole structures on solid supports is described. The immobilization of nitrobenzoic acid onto Merrifield resin and the subsequent treatment with alkenyl Grignard reagents delivered indole carboxylates bound to solid supports. In contrast to results in the liquid phase, ortho,ortho-unsubstituted nitroarenes also delivered indole moieties in good yields. Subsequent palladium-catalyzed reactions (Suzuki, Heck, Sonogashira, Stille) delivered, after cleavage, the desired molecules in moderate to good yields over four steps. The scope and limitations are presented.

SUBMITTER: Knepper K

PROVIDER: S-EPMC3458737 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Synthesis of diverse indole libraries on polystyrene resin - Scope and limitations of an organometallic reaction on solid supports.

Knepper Kerstin K Vanderheiden Sylvia S Bräse Stefan S

Beilstein journal of organic chemistry 20120726

The synthesis of diverse substituted indole structures on solid supports is described. The immobilization of nitrobenzoic acid onto Merrifield resin and the subsequent treatment with alkenyl Grignard reagents delivered indole carboxylates bound to solid supports. In contrast to results in the liquid phase, ortho,ortho-unsubstituted nitroarenes also delivered indole moieties in good yields. Subsequent palladium-catalyzed reactions (Suzuki, Heck, Sonogashira, Stille) delivered, after cleavage, the ...[more]

PMID: 23019447

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