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Asymmetric Syntheses of the Flavonoid Diels-Alder Natural Products Sanggenons C and O.

ABSTRACT: Metal-catalyzed, double Claisen rearrangement of a bis-allyloxyflavone has been utilized to enable a concise synthesis of the hydrobenzofuro[3,2-b]chromenone core structure of the natural products sanggenon A and sanggenol F. In addition, catalytic, enantioselective [4+2] cycloadditions of 2'-hydroxychalcones have been accomplished using B(OPh)3/BINOL complexes. Asymmetric syntheses of the flavonoid Diels-Alder natural products sanggenons C and O have been achieved employing a stereodivergent reaction of a racemic mixture (stereodivergent RRM) involving [4+2] cycloaddition.

SUBMITTER: Qi C

PROVIDER: S-EPMC4863937 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Asymmetric Syntheses of the Flavonoid Diels-Alder Natural Products Sanggenons C and O.

Qi Chao C Xiong Yuan Y Eschenbrenner-Lux Vincent V Cong Huan H Porco John A JA

Journal of the American Chemical Society 20160119 3

Metal-catalyzed, double Claisen rearrangement of a bis-allyloxyflavone has been utilized to enable a concise synthesis of the hydrobenzofuro[3,2-b]chromenone core structure of the natural products sanggenon A and sanggenol F. In addition, catalytic, enantioselective [4+2] cycloadditions of 2'-hydroxychalcones have been accomplished using B(OPh)3/BINOL complexes. Asymmetric syntheses of the flavonoid Diels-Alder natural products sanggenons C and O have been achieved employing a stereodivergent re ...[more]

PMID: 26735066

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