Use of a Traceless Activating and Directing Group for the Construction of Trifluoromethylpyrazoles: One-Pot Transformation of Nitroolefins and Trifluorodiazoethane.
We disclose an efficient one-pot transformation of trifluorodiazoethane and higher perfluorinated homologues with various nitroolefins. This method takes advantage of the nitro group as a traceless activating and directing group (TADG) that is released in the aromatization step to produce 4-substituted 3-perfluoroalkyl pyrazoles with complete regioselectivity. The potential of this method is further demonstrated by the synthesis of penthiopyrad.
Department of Chemistry, Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Tianjin University, Collaborative, Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300072, P. R. of China.
Zhen
Z
Chen
Department of Chemistry, Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Tianjin University, Collaborative, Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300072, P. R. of China.
Yan
Y
Zheng
Department of Chemistry, Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Tianjin University, Collaborative, Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300072, P. R. of China.
Jun-An
JA
Ma
diazo compounds; nitroolefins; pyrazoles; regioselectivity; traceless directing groups