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Updated: May 18, 2026

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Asymmetric synthesis of cyclopropanes with a monofluorinated quaternary stereocenter
Pavel Ivashkin1, Samuel Couve-Bonnaire, Philippe Jubault
1INSA de Rouen, UMR 6014 & FR 3038, C.O.B.R.A. Université de Rouen, 1 rue Tesnière, 76131 Mont-Saint-Aignan Cedex, France.
Abstract:
New chiral fluorinated reagents (N-(dibromofluoroacetyl)oxazolidinones) were easily synthesized and used in an asymmetric cyclopropanation process. The Michael initiated ring closure reaction provided chiral cyclopropanes bearing a fluorinated quaternary stereocenter. Various electron-deficient alkenes can be used to efficiently obtain chiral polysubtituted fluorinated cyclopropanes in good yields. Moderate to very good cis/trans ratios were obtained with a high level of diastereoselectivity for each isomer.
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