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Direct catalytic asymmetric and anti-selective vinylogous addition of butenolides to chromones.

ABSTRACT: An anti-selective catalytic asymmetric Michael-type vinylogous addition of β,γ-butenolides to chromones was developed. The catalyst system developed herein is characterized by tuning of the steric and electronic effects using a proper Biphep-type chiral ligand to invert the diastereoselection, and improvement of the catalyst turnover by a coordinative phenolic additive. The catalytic protocol renders potentially biologically active natural product analogs accessible in good yield with moderate diastereoselectivity and high enantiomeric purity, mostly greater than 99% ee.

SUBMITTER: Cui J

PROVIDER: S-EPMC8159409 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Direct catalytic asymmetric and anti-selective vinylogous addition of butenolides to chromones.

Cui Jin J Kumagai Naoya N Watanabe Takumi T Shibasaki Masakatsu M

Chemical science 20200622 27

An anti-selective catalytic asymmetric Michael-type vinylogous addition of β,γ-butenolides to chromones was developed. The catalyst system developed herein is characterized by tuning of the steric and electronic effects using a proper Biphep-type chiral ligand to invert the diastereoselection, and improvement of the catalyst turnover by a coordinative phenolic additive. The catalytic protocol renders potentially biologically active natural product analogs accessible in good yield with mod ...[more]

PMID: 34123001

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