Dibromofluoromethylation of aryl Grignard reagents with dibromodifluoromethane in the presence of LiBr

• The dibromofluoromethylation of aryl Grignard reagents was developed.
• The reaction proceeded via a difluorocarbene-mediated mechanism.
• α,α-Dibromo-α-fluorotoluene derivatives were obtained.

The dibromofluoromethylation of aryl Grignard reagents bearing electron-withdrawing groups with dibromodifluoromethane (CF2Br2) proceeded in the presence of LiBr. The reaction gave the corresponding α,α-dibromo-α-fluorotoluene derivatives through halogen exchange reaction of intermediate difluorobenzyl anions.

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