Hydrochloric Acid → 2-Chloro-6(dichloromethyl)pyridine

Participants

Reaction Conditions

Reaction Steps

Into a 250 milliliter (ml) flask fitted with a condenser, magnetic stirrer and dropping funnel were added 46.2 grams (g) (0.20 mole) of 2-chloro-6(trichloromethyl)pyridine, 30 g of methanol and 9.1 g (0.16 mole) of 20 mesh iron filings. The mixture was heated to 70° C. and 30 g of concentrated hydrochloric acid was added thereto over a 5 minute period. A slight exotherm occurred and the mixture was heated and maintained under reflux (83°-86° C.) for 1 hour. The reaction mixture was cooled to 45° C., and 50 ml of methylene chloride was added thereto. The mixture was filtered through diatomaceous earth and the filter cake washed thoroughly with water and then with methylene chloride. The filtrates were combined and the methylene chloride phase separated from the water phase. The product from a second run was combined with the above product mix and the mixture concentrated to a pot temperature of 95° C. at 15 millimeters of mercury (mm Hg). This residue was present in an amount of 74.5 g and melted at 48°-52° C. Analysis by gas-liquid chromatography (glc) showed a yield of 90.1 percent 2-chloro-6-(dichloromethyl)pyridine, 3.7 percent 2-chloro-6-(chloromethyl)pyridine and 1.7 percent 2 -chloro-6-(trichloromethyl)pyridine. The 2-chloro-6-(dichloromethyl)pyridine was recovered by recrystallization from heptane and melted at 53.3°-54.0° C.

Provenance & Evidence