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Synthesis of the bicyclic welwitindolinone core via an alkylation/cyclization cascade reaction.

ABSTRACT: Synthesis of an advanced welwitindolinone intermediate via an alkylation/cyclization reaction is reported. The key step involves a one pot Lewis acid-mediated alkylation of a silylketene aminal with a furan alcohol followed by an intramolecular cyclization. The reaction is stereoselective and takes place at low temperature. The cycloadduct was highly functionalized and contains the welwitindolinone core structure.

SUBMITTER: Brailsford JA

PROVIDER: S-EPMC2784123 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature

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Synthesis of the bicyclic welwitindolinone core via an alkylation/cyclization cascade reaction.

Brailsford John A JA Lauchli Ryan R Shea Kenneth J KJ

Organic letters 20091101 22

Synthesis of an advanced welwitindolinone intermediate via an alkylation/cyclization reaction is reported. The key step involves a one pot Lewis acid-mediated alkylation of a silylketene aminal with a furan alcohol followed by an intramolecular cyclization. The reaction is stereoselective and takes place at low temperature. The cycloadduct was highly functionalized and contains the welwitindolinone core structure. ...[more]

PMID: 19860385

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