Selective aromatic carbon–oxygen bond cleavage of trifluoromethoxyarenes: a trifluoromethoxy group as a convertible directing group

An efficient method for selective activation of aromatic C–O bonds in trifluoromethoxyarenes is developed. Upon treatment with a metallic sodium/chlorotrimethylsilane system, trifluoromethoxyarenes undergo reductive dealkoxylation to provide the corresponding arylsilanes. Also the synthetic applications of the present reactions combined with ortho-metallation are described.