Make Chlorotoluene (mixture of isomers) 1st step in making Pyrimethamine
In this video we demonstrate the synthesis of chlorotoluenes.
In the first process we react 4 moles of chlorine (2 moles of chlorine gas) with 500mL of toluene and 10g of steel wool in a flask with a reflux condenser. We then remove the steel wool and wash the chlorotoluenes with water and a saturated solution of sodium bicarbonate. Then we fractionally distill the organic layer to obtain chlorotoluenes in the boiling range of 135-170 Celsius.
In the second process we mix 125g of anhydrous ferrous chloride and 500mL of toluene. With vigorous stirring we add a total 160g of trichloroisocyanuric acid by 10g every 15 minutes or slower if the reaction begins to reflux. After the last addition the mixture is stirred overnight and then the organics are recovered using a dean stark trap and 500mL of water as the carrier solvent. The organic layer is then fractionally distilled to obtain chlorotoluenes as before.