Beschreibung:
<jats:title>Abstract</jats:title><jats:p>α‐Diazo esters are smoothly converted into the corresponding trifluoromethyl thio‐ or selenoethers by reaction with Me<jats:sub>4</jats:sub>NSCF<jats:sub>3</jats:sub> or Me<jats:sub>4</jats:sub>NSeCF<jats:sub>3</jats:sub>, respectively, in the presence of catalytic amounts of copper thiocyanate. This straightforward method gives high yields under neutral conditions at room temperature and is applicable to a wide range of functionalized molecules, including diverse α‐amino acid derivatives. It is well‐suited for the late‐stage introduction of trifluoromethylthio or ‐seleno groups into drug‐like molecules.</jats:p>