TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The iron(III) compound is an iron salt comprising ferric chloride (preferred), ferric nitrate, ferric sulfate, ferrous chloride, ferrous nitrate or ferrous sulfate.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Process: The process further comprises: (b) reacting a pyridine-3-carboxamide compound of formula (ID) with a with a base and a second halogenating agent to give a pyridine-3-amine compound of formula (IC); (c) reacting (IC) with a first halogenating agent in the presence of a hydrohalic acid to give (IB); isolating (A) by co-distillation with water vapor; and extracting (A) with a water immiscible solvent. The steps (a)-(c) are conducted in the same reaction vessel. The step (b) is conducted at a temperature of 20-80 degrees C, preferably 55-75 degrees C. Preferred Components: The first halogenating agent comprises bromine, N-bromosuccinimide, chlorine (preferred), N-chlorosuccinimide, hydrochloric acid and hydrogen peroxide, hypochlorous acid, hypobromous acid, alkali metal hypochlorites, alkali metal hypobromites or benzyltrimethyl ammonium tribromide. The second halogenating agent comprises chlorine, N-chlorosuccinimide, bromine, N-bromosuccinimide, hypochlorous acid, hypobromous acid, alkali metal hypochlorites, alkali metal hypobromites or benzyltrimethyl ammonium tribromide. The hydrohalic acid is hydrochloric acid, preferably sodium hypochlorite. EXAMPLE - 67.6 g of Chlorine was added to a mixture comprising 5.3-7 g of 3-aminopyridine, 503.9 g of 32% hydrochloric acid and 4.5 g of 40% aqueous ferric chloride at less than 25 degrees C to form 2-chloro-3-aminopyridine. Then 317 g of 40% aqueous ferric chloride and 100 g of water were added to 2-chloro-3-aminopyridine followed by slowly adding 151g of 40% aqueous sodium nitrite. The reaction temperature was kept at less than 30 degrees C during which time nitrogen gas was evolved. The reaction mixture was worked up to give 83.3 g of 2,3-dichloropyridine from 3-aminopyridine.