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Development of a merged conjugate addition/oxidative coupling sequence. Application to the enantioselective total synthesis of metacycloprodigiosin and prodigiosin R1.

ABSTRACT: A merged conjugate addition/oxidative coupling sequence that represents an efficient strategy for preparing structurally diverse pyrroles has been developed. Success of the method hinged upon the controlled oxidative coupling of unsymmetrical silyl bis-enol ether intermediates, formed by the 1,4-addition of a Grignard reagent with subsequent enolate trapping by a (chloro)silylenol ether. The process was applied to the first enantioselective syntheses of the biologically active pyrrolophane natural products, metacycloprodigiosin and prodigiosin R1.

SUBMITTER: Clift MD

PROVIDER: S-EPMC2762730 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature

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Development of a merged conjugate addition/oxidative coupling sequence. Application to the enantioselective total synthesis of metacycloprodigiosin and prodigiosin R1.

Clift Michael D MD Thomson Regan J RJ

Journal of the American Chemical Society 20091001 40

A merged conjugate addition/oxidative coupling sequence that represents an efficient strategy for preparing structurally diverse pyrroles has been developed. Success of the method hinged upon the controlled oxidative coupling of unsymmetrical silyl bis-enol ether intermediates, formed by the 1,4-addition of a Grignard reagent with subsequent enolate trapping by a (chloro)silylenol ether. The process was applied to the first enantioselective syntheses of the biologically active pyrrolophane natur ...[more]

PMID: 19754115

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