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Updated: Aug 6, 2025
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A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
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Excited-State Palladium-Catalyzed α-Selective C1-Ketonylation
Gaoyuan Zhao1, Upasana Mukherjee1, Lin Zhou2
1Department of Chemistry and Institute of Chemical Biology and Drug Discovery, the State University of New York at Stony Brook, Stony Brook, New York 11794.
CCS Chemistry
|March 15, 2023
Summary
This study introduces a new palladium-catalyzed method for synthesizing alpha-ketonyl sugars, which are important carbohydrate mimetics. This efficient strategy provides access to valuable C-glycosides for drug discovery.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
- Carbohydrate Chemistry
Background:
- C-Glycosides are crucial carbohydrate mimetics with applications in natural products, bioactive compounds, and pharmaceuticals.
- Stereoselective synthesis of C-glycosides presents a significant challenge in organic chemistry.
Purpose of the Study:
- To develop an efficient and stereoselective method for synthesizing alpha-ketonyl C-glycosides.
- To explore a novel excited-state palladium-catalyzed C-ketonylation strategy.
Main Methods:
- Utilized readily available 1-bromosugars as starting materials.
- Employed an excited-state palladium-catalyzed reaction for alpha-selective C-ketonylation.
- Investigated reaction mechanisms through preliminary experimental and computational studies.
Main Results:
- Achieved excellent alpha-selectivity in the C-ketonylation of sugars.
- Demonstrated mild reaction conditions compatible with diverse functional groups and complex molecules.
- Synthesized alpha-ketonyl sugars as versatile precursors for beta-isomers and other C-glycosides.
Conclusions:
- The developed method offers a straightforward and efficient route to alpha-ketonyl C-glycosides.
- The proposed radical pathway provides mechanistic insights into the reaction.
- This work expands the accessibility of C-glycosides, broadening their chemical and patent spaces.
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