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Updated: Jul 19, 2025

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Pyridinium-Masked Enol as a Precursor for Constructing Alpha-Fluoromethyl Ketones
Jijun Xu1, Yi Li1, Xuanyu Zhu1
1Joint Laboratory of International Cooperation of Resource Chemistry of Ministry of Education, Shanghai Frontiers Science Center of Biomimetic Catalysis, Shanghai Normal University, Shanghai 201418, China.
Abstract:
We present herein a pyridinium-masked enol as a versatile platform to produce ketones bearing tri-, di-, and monofluoromethyl in the presence of [Ir(dF(Me)ppy)]2(dtbbpy)]PF6 under blue light (455 nm) irradiation. By simply changing the F-source, α-trifluoromethyl ketones, α-difluoromethyl ketones, and α-monofluoromethyl ketones could be easily prepared in moderate to excellent yields in one step, making it a practical tool for the synthesis of fluorine-containing ketones. In addition, the pyridinium-masked enol could also be extended to the synthesis of sulfonyl ketones. The findings of the present protocol contribute to the arsenal of fluorine chemistry and might have potential applications in the pharmaceutical and agrochemical industries.
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