Photocatalytic site-selective C-H difluoroalkylation of aromatic aldehydes

Chem Commun (Camb). 2020 Feb 4;56(10):1497-1500. doi: 10.1039/c9cc09586a.

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.