The compounds with trifluoromethyl group are ubiquitous in pharmaceuticals, agrochemicals and materials. In view of their wide application, synthetic organic chemists are devoted to seek efficient methods for the incorporation of trifluoromethyl group into molecular frameworks and the discoveries of trifluoromethylating reagents. In this context, trifluoroacetic acid is undoubtedly an ideal alternatives due largely to their ready availability.
Prof. SU Weiping from Fujian Institute of Research on the Structure of Matter (FJIRSM) of the Chinese Academy of Sciences(CAS), in cooperation with Prof. LI Yadong from Tsinghua University, just reported an effective method for direct C-H trifluoromethylation of nonactivated (hetero)arenes with trifluoroacetic acid under room temperature.
The established approach employs cheap trifluoroacetic acid as trifluoromethyl reagent, clean light as an energy source, non-toxic and environmental friendly TiO2 as a photocatalyst.
What deserves to be mentioned is that a novel mechanism was proposed in this process based on detailed mechanistic investigation, in which no additional catalyst is involved, the proton in the reaction system act as oxidant to release hydrogen in the catalytic cycle.
This study demonstrated the unique potential of photocatalysis in the direct functionalization of C-H bonds without the addition of an oxidizing agent, and fully met the requirements of atomic economy.
This study was financially supported by the National Natural Science Foundation of China, the CAS/SAFEA International Partnership Program for Creative Research Teams and the Strategic Priority Research Program of the Chinese Academy of Sciences.
The findings have been published on Nat. Commun. with the title of " Photo-driven redox-neutral decarboxylative carbon-hydrogen trifluoromethylation of (hetero)arenes with trifluoroacetic acid".
Photocatalytic trifluoromethylation of arenes with trifluoroacetic acid. (Image by Prof. SU’s Group)
Contact:
Prof. SU Weiping
Fujian Institute of Research on the Structure of Matter
Chinese Academy of Sciences
Email: wpsu@fjirsm.ac.cn
