Rhodium-catalysed C(sp(2))-C(sp(2)) bond formation via C-H/C-F activation
Panpan Tian1, Chao Feng2, Teck-Peng Loh2
1Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China.
Abstract:
Fluoroalkenes represent a class of privileged structural motifs, which found widespread use in medicinal chemistry. However, the synthetic access to fluoroalkenes was much underdeveloped with previous reported methods suffering from either low step economy or harsh reaction conditions. Here we present a Rh(III)-catalysed tandem C-H/C-F activation for the synthesis of (hetero)arylated monofluoroalkenes. The use of readily available gem-difluoroalkenes as electrophiles provides a highly efficient and operationally simple method for the introduction of α-fluoroalkenyl motifs onto (hetero)arenes under oxidant-free conditions. Furthermore, the employment of alcoholic solvent and the in-situ generated hydrogen fluoride are found to be beneficial in this transformation, indicating the possibility of the involvement of hydrogen bond activation mode with regards to the C-F bond cleavage step.
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