A Series of Deoxyfluorination Reagents Featuring OCF2 Functional Groups
Shiyu Zhao, Yong Guo*, Zhaoben Su, Wei Cao, Chengying Wu and Qing-Yun Chen*
*Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P. R. China,
Email: yguosioc.ac.cn, chenqy
sioc.ac.cn
S. Zhao, Y. Guo, Z. Su, W. Cao, C. Wu, Q.-Y. Chen, Org. Lett., 2020, 22, 8634-8637.
DOI: 10.1021/acs.orglett.0c03238
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Abstract
Perfluoroalkyl ether carboxylic acids (PFECAs) are alternatives for perfluoroalkyl substances with the goal of protecting the environment. PFECAs decompose to carbonic difluoride (COF2), which can be used for deoxyfluorination reactions of alcohols to provide alkyl fluorides in very good yields.
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proposed reaction pathway
Details
The document discusses a new series of deoxyfluorination reagents featuring OCF2 functional groups derived from perfluoroalkyl ether carboxylic acids (PFECAs). These reagents enable the efficient conversion of alcohols to alkyl fluorides, which are valuable in medicinal chemistry due to fluorine's unique properties. The study highlights the environmental concerns associated with PFECAs and their decomposition products, proposing a method to utilize these byproducts effectively. The researchers optimized reaction conditions using 4-phenyl-1-butanol as a model substrate, achieving up to 97% yield of alkyl fluorides. The process involves in situ generation of carbonic difluoride (COF2) from the thermal degradation of PFO2HxA salts. The method tolerates a wide range of functional groups and is applicable to various primary and secondary alcohols, with moderate to excellent yields. The study also explores the scalability of the reaction and confirms the SN2 mechanism through control experiments. This approach not only provides an efficient synthetic route for alkyl fluorides but also offers a way to reclaim and add value to fluorinated byproducts from industrial processes.
Key Words
ID: J54-Y2020