Photocatalytic site-selective C-H difluoroalkylation of aromatic aldehydes
Wei-Ke Tang1, Fei Tang, Jun Xu
1School of Chemistry and Chemical Engineering, School of Food and Biological Engineering, Institute of Industry & Equipment Technology, Hefei University of Technology, Hefei 230009, P. R. China. junxu@hfut.edu.cn fengyisi@hfut.edu.cn hjxu@hfut.edu.cn.
Abstract:
The direct photocatalyzed para-selective CAr-H difluoroalkylation of aromatic aldehyde derivatives has been accomplished using a newly explored catalytic system. In addition, when using para-substituted benzaldehydes as substrates, ortho-selective CAr-H difluoroalkylation was also accomplished. It is worth noting that all the above site-selectivity is opposite to traditional Friedel-Crafts reactions of aromatic aldehydes. The preliminary mechanistic investigations indicate that an electrophilic difluoroalkyl radical is involved in the catalytic cycle.
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