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Updated: Jun 10, 2025
07:06
A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
8.1K
Organocatalytic Strategy for a Formal 1,6-Conjugate Hydroxylation.
Sifeddine Mohamed Aouina1, Anthony Lapray1, Jean-Valère Naubron2
1INSA Rouen Normandie, Univ Rouen Normandie, CNRS, Normandie Univ, COBRA UMR 6014, INC3M FR 3038, F-76000 Rouen, France.
Organic Letters
|October 18, 2024
Summary
Organocatalysis enabled a novel sulfa-Michael reaction using hexafluoro isopropyl acrylate. This led to a one-pot sequence involving amidation, oxidation, and a [2,3]-sigmatropic rearrangement, achieving asymmetric hydroxylation.
Area of Science:
- Organic chemistry
- Asymmetric synthesis
Background:
- Vinylogous hexafluoro isopropyl acrylate platforms offer unique reactivity.
- Organocatalysis is a powerful tool for selective transformations.
Purpose of the Study:
- To develop a regio- and enantioselective sulfa-Michael reaction.
- To establish a one-pot synthetic sequence for complex molecule construction.
Main Methods:
- Organocatalytic sulfa-Michael addition to vinylogous hexafluoro isopropyl acrylate.
- Sequential one-pot amidation, oxidation, and Mislow-Bravermann-Evans rearrangement.
- Chirality transfer mechanisms were investigated.
Main Results:
- Achieved high regio- and enantioselectivity in the sulfa-Michael reaction.
- Successfully integrated multiple transformations into a single pot.
- Demonstrated a 1,3-chirality transfer during the sigmatropic rearrangement.
- Established a formal asymmetric 1,6-hydroxylation sequence.
Conclusions:
- The developed methodology provides an efficient route to complex chiral molecules.
- Vinylogous hexafluoro isopropyl acrylate is a versatile building block for asymmetric synthesis.
- The one-pot strategy highlights the potential of cascade reactions in organic synthesis.
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