title: Radical Addition of Hydrazones by α-Bromo Ketones To Prepare 1,3,5-Trisubstituted Pyrazoles via Visible Light Catalysis.
abstract: A novel efficient tandem reaction of hydrazones and α-bromo ketones is reported for the preparation of 1,3,5-trisubstituted pyrazoles by visible light catalysis. In this system, the monosubstituted hydrazones show wonderful reaction activity with alkyl radicals, generated from α-bromo ketones. A radical addition followed by intramolecular cyclization affords the important pyrazole skeleton in good to excellent yields. This efficient strategy under mild conditions with wide group tolerance provides a potential approach to the 1,3,5-trisubstituted pyrazoles.
authors.affiliation: Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry and University of Chinese Academy of Sciences, Chinese Academy of Sciences , Beijing 100190, P. R. China.
authors.forename: Xiu-Wei
authors.initials: XW
authors.lastname: Fan
authors.affiliation: Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry and University of Chinese Academy of Sciences, Chinese Academy of Sciences , Beijing 100190, P. R. China.
authors.forename: Tao
authors.initials: T
authors.lastname: Lei
authors.affiliation: Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry and University of Chinese Academy of Sciences, Chinese Academy of Sciences , Beijing 100190, P. R. China.
authors.forename: Chao
authors.initials: C
authors.lastname: Zhou
authors.affiliation: Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry and University of Chinese Academy of Sciences, Chinese Academy of Sciences , Beijing 100190, P. R. China.
authors.forename: Qing-Yuan
authors.initials: QY
authors.lastname: Meng
authors.affiliation: Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry and University of Chinese Academy of Sciences, Chinese Academy of Sciences , Beijing 100190, P. R. China.
authors.forename: Bin
authors.initials: B
authors.lastname: Chen
authors.affiliation: Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry and University of Chinese Academy of Sciences, Chinese Academy of Sciences , Beijing 100190, P. R. China.
authors.forename: Chen-Ho
authors.initials: CH
authors.lastname: Tung
authors.affiliation: Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry and University of Chinese Academy of Sciences, Chinese Academy of Sciences , Beijing 100190, P. R. China.
authors.forename: Li-Zhu
authors.initials: LZ
authors.lastname: Wu