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Asymmetric Synthesis of β-Substituted α-Methylenebutyro- lactones via TRIP-Catalyzed Allylation: Mechanistic Studies and Application to the Synthesis of (S)-(-)-Hydroxymatairesinol.

ABSTRACT: Asymmetric allylation of (hetero)aromatic aldehydes by a zinc(II)-allylbutyrolactone species catalyzed by a chiral BINOL-type phosphoric acid gave β-substituted α-methylenebutyrolactones in 68 to >99% ee and 52-91% isolated yield. DFT studies on the intermediate Zn²⁺-complex - crucial for chiral induction - suggest a six-membered ring intermediate, which allows the phosphoric acid moiety to activate the aldehyde. The methodology was applied to the synthesis of the antitumour natural product (S)-(-)-hydroxymatairesinol.

SUBMITTER: Fuchs M

PROVIDER: S-EPMC3883096 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature

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Asymmetric Synthesis of β-Substituted α-Methylenebutyro- lactones via TRIP-Catalyzed Allylation: Mechanistic Studies and Application to the Synthesis of (S)-(-)-Hydroxymatairesinol.

Fuchs Michael M Schober Markus M Orthaber Andreas A Faber Kurt K

Advanced synthesis & catalysis 20130829 13

Asymmetric allylation of (hetero)aromatic aldehydes by a zinc(II)-allylbutyrolactone species catalyzed by a chiral BINOL-type phosphoric acid gave β-substituted α-methylenebutyrolactones in 68 to >99% ee and 52-91% isolated yield. DFT studies on the intermediate Zn2+-complex - crucial for chiral induction - suggest a six-membered ring intermediate, which allows the phosphoric acid moiety to activate the aldehyde. The methodology was applied to the synthesis of the antitumour na ...[more]

PMID: 24415960

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