text: Halo ketones take part in several reaction types, especially since they are bifunctional, with two electrophilic sites (α-carbon and carbonyl carbon). In one manifestation of this duality, they are precursors to heterocycles. Thiazoles arise from reaction of  chloroacetone with thioamides.2-Aminothiazoles are similarly produced by reaction of 2-chloroketones with thioureas. Pyrroles may be synthesized by reaction of halo ketones with dicarbonyls and ammonia in the Hantzsch pyrrole synthesis.