A Simple and Cost‐Effective Method for the Regioselective Deuteration of Phenols

Abstract A highly effective and operationally simple method for the deuteration of phenols using NaOH as a catalyst and D 2 O as the deuterium source is presented. A high regioselectivity for the ortho and/or para hydrogens relative to the oxygen atom was achieved, as well as a high degree of deuterium incorporation. The method also has a high functional‐group tolerance, and allowed the deuteration of complex pharmaceutically interesting substrates.