2-Substituted 4-(Trifluoromethyl)phenols by Directed ortho-Lithiation

Abstract

A broad variety of 2-substituted 4-(trifluoromethyl)phenols can be prepared in a large scale by o-lithiation and reaction with electrophiles in good to excellent yields. The key for the selectivity is the superior ortho-directing effect of the THP-protected hydroxy group (OTHP) as compared to the CF₃-group.

arylations - electrophilic aromatic substitutions - lithiation - protecting groups - 4-(trifluoromethyl)phenol

References

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