5-Fluoro-2-chloropyrimidine (CAS number 62802-42-0) is derived from pyrimidine, an aromatic heterocyclic 6-membered ring with two nitrogen atoms at positions 1 and 3. 5-Fluoro-2-chloropyrimidine also has a fluorine and a chlorine substituents at the para-position, making it useful for synthesizing linear molecules. With two nitrogens in the ring, 5-fluoro-2-chloropyrimidine is π electron deficient which facilitates nucleophilic aromatic substitution. 2-Chloro-5-fluoropyrimidine is often used to synthesize active pharmaceutical ingredients (APIs), such as antibiotics.
5-Fluoro-2-chloropyrimidine is also used to synthesize ligands for iridium complexes. The iridium complexes show great external quantum efficiency exceeding 29.5%.