Visible-Light-Induced Perfluoroalkylation/Cyclization to Access Perfluoroalkylated Pyrazol-5-ones via
Sheng Yu1, Yangjian Cheng1, Guocheng Yin1
1School of Petrochemical Engineering, Changzhou University, Changzhou 213164, P. R. China.
Abstract:
A halogen-bond-based electron donor-acceptor (EDA) complex-promoted perfluoroalkylative cyclization of N-phenylmethacrylohydrazides was developed. In this reaction, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) functions as an electron donor and interacts with perfluoroiodocarbon to form the EDA complex, which produces a perfluoroakyl radical after irradiation by blue LEDs. A series of perfluoroalkylated pyrazol-5-ones were obtained in moderate to good yields under mild conditions without the requirement of any external photocatalyst.
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