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Updated: Jul 28, 2025
Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Anion-accelerated asymmetric Nazarov cyclization: access to vicinal all-carbon quaternary stereocenters
Cody F Dickinson1, Glenn P A Yap2, Marcus A Tius1
1Department of Chemistry, University of Hawaii at Manoa, Honolulu, Hawaii 96822, USA. tius@hawaii.edu.
Abstract:
We have developed a catalytic asymmetric Nazarov cyclization that results in the formation of two contiguous all-carbon quaternary stereocenters in high yield with excellent levels of asymmetric induction. This method requires no catalyst recognition elements in the starting materials that are simple diketoesters. Geometrically pure E or Z isomers of the starting material lead to diastereomerically pure products with high enantioselectivity because the species that undergoes cyclization is a rhodium enolate that is configurationally stable.
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