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Vanadium-Catalyzed Selective Oxidative Homocoupling of Alkenyl Phenols to Synthesize Lignan Analogs.

ABSTRACT: The oxidative homocoupling of para-alkenyl phenols and subsequent trapping of the resulting quinone methide with a variety of oxygen and nitrogen nucleophiles was achieved. Both ?-? and ?-O coupling isomers can be synthesized via either C-C coupling and two nucleophilic additions of one water molecule (?-? isomer) or C-O coupling followed by one nucleophilic addition of a water molecule (?-O isomer), respectively. Selectivity between these outcomes was achieved by leveraging understanding of the mechanism. Specifically, a qualitative predictive model for the selectivity of the coupling was formulated based on catalyst electronics, solvent polarity, and concentration.

SUBMITTER: Neuhaus WC

PROVIDER: S-EPMC7043397 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Vanadium-Catalyzed Selective Oxidative Homocoupling of Alkenyl Phenols to Synthesize Lignan Analogs.

Neuhaus William C WC Jemison Adriana L AL Kozlowski Marisa C MC

ACS catalysis 20191023 12

The oxidative homocoupling of <i>para</i>-alkenyl phenols and subsequent trapping of the resulting quinone methide with a variety of oxygen and nitrogen nucleophiles was achieved. Both β-β and β-O coupling isomers can be synthesized via either C-C coupling and two nucleophilic additions of one water molecule (β-β isomer) or C-O coupling followed by one nucleophilic addition of a water molecule (β-O isomer), respectively. Selectivity between these outcomes was achieved by leveraging understanding ...[more]

PMID: 32104612

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