3-Fluorophenylacetonitrile shows how. It looks simple: a fluorinated benzene ring, a CH2 group, and a nitrile. But the nitrile does something useful. It helps make the neighboring carbon chemically accessible for building new carbon-carbon bonds.
And chemists can use that reactivity to construct something much less obvious: a cyclopropane. This chemistry appears in established synthetic routes to lemborexant, a dual orexin receptor antagonist used to treat insomnia.
Global Chemical Database